The Battle of Yarmouk (Arabic: معركة اليرموك, also spelled Yarmuk, Yarmuq or Hieromyax) was comprised of a series of engagements between the Rashidun Caliphate and the Byzantine Empire over six days in August 636, near the Yarmouk River, along what is today the border between Syria and Jordan, south-east of the Sea of Galilee. Other names In Arabic, the month is called أغسطسص ʾUġusṭuṣ or آب ʾĀb; usage varies from place to place and Events By Place Byzantine Empire August 20 — Battle of Yarmuk: Khalid ibn al-Walid 's victory against the The Yarmouk River ( Arabic: نهر اليرموك, " Nahr Al-Yarmuk " Hebrew: נהר הירמוך " Nehar HaYarmukh " The Rightly Guided Caliphs or The Righteous Caliphs ( ar الخلفاء الراشدون) is a term used in Sunni Islam to refer to the first See also Names of the Levant The Levant (lə'vænt is a geographical term that denotes a large area in Western Asia, roughly bounded on the north by the The Rashidun Caliphate Army or Rashidun army was the primary military body of the Rashidun Caliphate 's Armed forces during the Muslim Heraclius, or Herakleios (Flavius Heraclius Augustus;) (c 575 - February 11, 641) was a Byzantine Emperor, who ruled the East Killed in action ( KIA or K I A) is a casualty classification generally used by militaries to describe the deaths of their own forces by other Theodore Trithyrius was a treasurer of the state of Syria and a military commander working for the the Byzantine emperor Heraclius. Jabalah ibn al-Aiham was the last ruler of the Ghassanid state in Syria and Jordan in the seventh century AD Killed in action ( KIA or K I A) is a casualty classification generally used by militaries to describe the deaths of their own forces by other Killed in action ( KIA or K I A) is a casualty classification generally used by militaries to describe the deaths of their own forces by other Khālid ibn al-Walīd (592-642 ( خالد بن الوليد) also known by Sunnis as Sayf-'ullah al-Maslul (the Drawn Sword of God, God's Withdrawn ˤAmr ibn al-ˤĀs (عمرو بن العاص (born c583 - d January 6, 664 CE was an Arab Military commander who is most noted for leading Yazid ibn Abu Sufyan ( يزيد بن أبو سفيان) was one of the companions of Muhammad. Arabic (ar الْعَرَبيّة (informally ar عَرَبيْ) in terms of the number of speakers is the largest living member of the Semitic language The Rightly Guided Caliphs or The Righteous Caliphs ( ar الخلفاء الراشدون) is a term used in Sunni Islam to refer to the first Other names In Arabic, the month is called أغسطسص ʾUġusṭuṣ or آب ʾĀb; usage varies from place to place and Events By Place Byzantine Empire August 20 — Battle of Yarmuk: Khalid ibn al-Walid 's victory against the The Yarmouk River ( Arabic: نهر اليرموك, " Nahr Al-Yarmuk " Hebrew: נהר הירמוך " Nehar HaYarmukh " Syria ( سوريّة or) officially the Syrian Arab Republic (Arabic ar الجمهورية العربية السورية Jordan, officially the Hashemite Kingdom of Jordan (الأردنّ al-Urdunn) is an Arab country in Southwest Asia spanning the southern The Sea of Galilee, also Sea of Genneseret, Lake Kinneret or Lake Tiberias (Hebrew ים כנרת) (Arabic بحيرة طبريا) The battle marked the first great wave of Islamic conquests after the death of Muhammad, heralding the rapid advance of Islam into the then Christian Levant. The initial Arab Muslim conquests (632–732 (فتح Fatah, literally opening, also referred to as the Islamic conquests or Arab IMPORTANT PLEASE READ ##### For all questions relating to the addition of (pbuh peace be upon him or other honorifics For other meanings including people named 'Islam' see Islam (disambiguation. A Christian is a person who adheres to Christianity, a monotheistic Religion centered on the life and teachings of Jesus of Nazareth See also Names of the Levant The Levant (lə'vænt is a geographical term that denotes a large area in Western Asia, roughly bounded on the north by the The battle is also considered to be one of Khalid ibn al-Walid's most decisive victories, and cemented his reputation as a great tactician and cavalry commander. Khālid ibn al-Walīd (592-642 ( خالد بن الوليد) also known by Sunnis as Sayf-'ullah al-Maslul (the Drawn Sword of God, God's Withdrawn 
Prophet Mohammad died in June 632, and Abu Bakr was appointed Caliph and his political successor. IMPORTANT PLEASE READ ##### For all questions relating to the addition of (pbuh peace be upon him or other honorifics Troubles emerged soon after Abu Bakr's succession. Early life Abu Bakr was born at Mecca some time in the year 573 CE, in the Banu Taym branch of the Quraysh tribe Several Arabic tribes revolted against Abu Bakr. This was the start of the Ridda wars (Arabic for the Wars of Apostasy). Arabic (ar الْعَرَبيّة (informally ar عَرَبيْ) in terms of the number of speakers is the largest living member of the Semitic language Abu Bakr declared war against the rebels, The Campaign of the Apostasy was fought and completed during 632, and by 633, with Arabia united under the central authority of the Caliph at Medina. Events By Place Europe Oswald of Bernicia becomes Bretwalda. Osric becomes king of Deira. Once the rebellions had been put down, Abu Bakr began a war of conquest, Abu Bakr began with Iraq, the richest province of the Persian Empire. For a topic outline on this subject see List of basic Iraq topics. The Sassanid Empire or Sassanian Dynasty or Sassanian Dynasty (ساسانیان) is the name used for the third Iranian dynasty and the second Persian empire He sent his most brilliant general Khalid ibn al-Walid to invade the Sassanid Persian Empire. After successful campaigns against Sassanid Persians and conquest of Iraq, Abu Bakr's confidence built up, once Khalid established his stronghold on Iraq, Abu Bakr issued a call to arms for the invasion of Syria in February 634. For a topic outline on this subject see List of basic Iraq topics. The muslim invasion of Syria was a carefully planned, coordinated and organised series of military operation using strategy well able to deal with Byzantine defensive measures. Abu Bakr organised the army in to four corps, each with its own commander and objective, this tactics of penetrating by several self-sufficient armies eliminated the traditional distinction between "front" and "rear".  These armies soon proved to be small, and called for reinforcement when when Byzantine emperor Heraclius, disturbed by this Arabian movement, ent in a foray, his brother Theodore to lead an army of Syrian garrisons against the invaders. This is a list of the Emperors of the Eastern Roman Empire, commonly known as the Byzantine Empire by modern historians Heraclius, or Herakleios (Flavius Heraclius Augustus;) (c 575 - February 11, 641) was a Byzantine Emperor, who ruled the East Khalid was sent by Abu Bakr from Iraq to Syria with reinforcement and to lead the invasion. The battle thus fought was at Ajnadayn, were byzantines were decisively defeated. The Battle of Ajnadayn, fought on July 30, 634, was the first major Pitched battle between the Byzantine Empire and the Rashidun Caliphate Damascus fall in september 634, followed by Battle of Fahl were the last strong garrison of Palestine was defeated and routed. Damascus was conquered by the Rashidun army after a siege lasting about one month from 21 August to 19 September 634 AD The Battle of Fahl or Battle of Pella was a Byzantine-Arab battle fought between the Rashidun army under Khalid ibn al-Walid ( The Sword Caliph Abu Bakr died in 634, making Umar his successor. Umar (a=عمر بن الخطاب|t=`Umar ibn al-Khattāb c 581-83 CE &ndash 7 November, 644) also known as Umar the Great or Omar the Great While Abu Bakr had been successful in invading Syria, Umar was determined to extend the reach of his kingdom and continued the conquest deeper into Syria.  Though previous campaigns led by Khalid ibn al-Walid were successful, he was never in the good books of Umar and was replaced by Abu Ubaidah ibn al-Jarrah. Khālid ibn al-Walīd (592-642 ( خالد بن الوليد) also known by Sunnis as Sayf-'ullah al-Maslul (the Drawn Sword of God, God's Withdrawn  The Arabs had already secured southern Palestine now advanced up the trade route that went east of Jordan and over to Damascus and Orontes valley. This article is about the Jordan River and its valley in western Asia See Orontid dynasty for the Armenian kings and satraps called Orontes Tiberias and Baalbek fell into the hands of the Arabs without much struggle and the Muslims Conquered Emesa later that year. Tiberias ( British English: /taɪˈbɪəriæs -əs/ American English: /taɪˈbɪriəs/ טְבֶרְיָה Tverya; طبرية Ṭabariyyah Baalbek (بعلبك is a town in the Bekaa Valley of Lebanon, altitude 1170 m (3850 ft situated east of the Litani River. The Battle of Emesa was fought in 272 between Roman and Palmyran forces From there on, the Muslims continued their conquest across the Levant. See also Names of the Levant The Levant (lə'vænt is a geographical term that denotes a large area in Western Asia, roughly bounded on the north by the 
By 635, Muslims had conquered most of Palestine and southern Syria and with Emesa under their power, the Muslims were just a march away from Aleppo, a Byzantine stronghold and Antioch where Heraclius resided. Palestine is a name which has been widely used since Roman times to refer to the region between the Mediterranean Sea and the Jordan River. For other meanings see Aleppo (disambiguation. Halab redirects here for other meanings see Halab (disambiguation. Antioch on the Orontes (Ἀντιόχεια ἡ ἐπὶ Δάφνῃ Ἀντιόχεια ἡ ἐπὶ Ὀρόντου or Ἀντιόχεια ἡ Μεγάλη Antiochia ad Orontem also Now seriously alarmed by this debacle, Heraclius started to plan for a counter-attack to roll back the lost region. Emperor Heraclius assembled large army in northern Syria and Antioch in late-635 to halt the Arab invasion. Events By Topic Religion Saint Aidan founds Lindisfarne in Northumbria, England Preparations started in late 635, and by May 636, a large force was put under arms and was concentrated at Antioch and northern Syria. Antioch on the Orontes (Ἀντιόχεια ἡ ἐπὶ Δάφνῃ Ἀντιόχεια ἡ ἐπὶ Ὀρόντου or Ἀντιόχεια ἡ Μεγάλη Antiochia ad Orontem also The assembled army consisted of contingents of Byzantines, Slavs, Franks, Georgians, Armenians and Christian Arabs,. The Franks or Frankish people (Franci or gens Francorum) were West Germanic tribes first identified in the 3rd century as an Ethnic group The Georgians (ქართველები kartvelebi) are a Nation and Ethnic group originating in the Caucasus, the oldest group of the The Armenians (Հայեր Hayer) are a Nation and Ethnic group originating in the Caucasus and in the Armenian Highlands A large This force was organized into five armies, Joint leader of which was Theodore Trithourios the Sakellarios, and Vahan, the king of Armenia — who commanded a purely Armenian army, was the field commander, Buccinator (Qanateer), a Slavic prince commanded the Slavs and Jabalah ibn al-Aiham, king of the Ghassanid Arabs, commanded an exclusively Christian Arab force. Armenia (Հայաստան transliterated: Hayastan,) officially the Republic of Armenia (Հայաստանի Հանրապետություն Hayastani Jabalah ibn al-Aiham was the last ruler of the Ghassanid state in Syria and Jordan in the seventh century AD The remaining contingents (all European), were placed under Gregory and Dairjan. . Heraclius himself supervised operation from Antioch. Byzantine sources tells about the presence of Niketas son of Shahrbaraz among the commanders but it is not certain which army he commanded.  At that time, the Rashidun army was split in four groups: one under Amr ibn al-Aas in Palestine, one under Shurahbil in Jordan, one under Yazid ibn Abu Sufyan at Damascus-Caesarea region and the last one under Abu Ubaidah ibn al-Jarrah along with Khalid ibn al-Walid at Emesa. ˤAmr ibn al-ˤĀs (عمرو بن العاص (born c583 - d January 6, 664 CE was an Arab Military commander who is most noted for leading Jordan, officially the Hashemite Kingdom of Jordan (الأردنّ al-Urdunn) is an Arab country in Southwest Asia spanning the southern Yazid ibn Abu Sufyan ( يزيد بن أبو سفيان) was one of the companions of Muhammad. Damascus ( دمشق,, also commonly known as الشام ash-Shām) is the capital and largest city of Syria. Caesarea (קיסריה Qesarya قيسارية pronounced Kaysaria) is a town in Israel on the outskirts of Caesarea Maritima, the ancient port Khālid ibn al-Walīd (592-642 ( خالد بن الوليد) also known by Sunnis as Sayf-'ullah al-Maslul (the Drawn Sword of God, God's Withdrawn For military actions near the city see Battle of Homs. Homs ( حمص,, anciently called Emesa (ἡ Ἔμεσα or "La Chamelle" Being geographically divided up in each direction, Heraclius sought to exploit this situation and planned to attack and destroy each of these Muslim corps separately by putting a large concentration of troops against each of them in turn. Thus, reinforcements were sent to Caesarea under Heraclius’s son Constantine, probably to tie down Yazid's forces there, which were besieging Caesarea, so that it would not move to join other Muslim corps to help them. The rest of the Imperial Army was to operate on the following plan:
The imperial army was launched from Antioch and northern Syria some time in the middle of June 636.
It was at Shaizar, through Roman prisoners, that the Muslims first came to know of the preparations being made by Heraclius. Alert to the possibility of being caught with separated forces that could be destroyed in detail, as Heraclius indeed planned, Khalid, in a council of war, advised Abu Ubaidah to pull back from northern and central Syria, as well as from Palestine and concentrated the entire Rashidun army at one place. Abu Ubaidah ordered the concentration of trops in the vast plain near Jabiya which was suitable for cavalry charge and from there it would be easier for the caliph to send reinforcements and thus a strong, united force could be fielded against the Byzantine armies. The position also was beneficiary, due to its close proximity to Najd (a Rashidun stronghold), in case of retreat.  Ibn al-Jarrah, Muslim's commander in chef, thus ordered the commanders to surrender the territory under their control and withdraw the army to Jabiya. In addition, he ordered the commanders to return the jizya (tribute) to the people who had paid it.  At first muslims concentrated at Jabiya, but were subjected at raids from pro-Byzantine Ghassanid forces, the region was also not suitable to camp as there was a strong byzantine garrison in Caeseara that could attack Muslims from rear while they were frontly held by the Byzantine army. On Khalid’s advise they retreated to Dara’ah and dayr Ayyub covering the gap between Yarmouk Gorges and Harra lava plains established a line of camps in the eastern part of the plain of Yarmuk. No major conflict occurred except for a minor skirmish between Khalid's elite light cavalry Mobile guard and Byzantine Advance guard. The Mobile guard ( متحرك طليعة), was a Light cavalry of Rashidun army during the Muslim conquest of Syria, that remained under the
The battlefield lies about 65-kilometres south-west of the Golan heights, an upland region currently on the frontier between Israel, Jordan and Syria, east of the Sea of Galilee. Borders of Israel The Golan Heights ( الجولان al-Jawlān, הגולן ha-Golan) is a strategic Plateau and mountainous For a topic outline on this subject see List of basic Israel topics. Jordan, officially the Hashemite Kingdom of Jordan (الأردنّ al-Urdunn) is an Arab country in Southwest Asia spanning the southern The Sea of Galilee, also Sea of Genneseret, Lake Kinneret or Lake Tiberias (Hebrew ים כנרת) (Arabic بحيرة طبريا)  The battle was fought on the plain of Yarmouk which was enclosed on its western and southern edges by a deep ravine, known as Wadi-ur-Raqqad with banks about 30 m deep. This ravine joins the Yarmouk River, a tributary of the Jordan River on its south. This article is about the Jordan River and its valley in western Asia The stream had very steep banks from 10–30 m deep.  On the north lay the Jabiya road and to the east lie the Azra hills, although these hills were outside the actual field of battle. Strategically there was only one prominence in the battlefield – a 100 m high elevation known as the hill of Jamu'a (meaning gathering). For the Muslim troops concentrated on it, it gave a good view of the plain of Yarmouk. What now is a ravine on the west of the battlefield was accessible at a few places in 636 AD, and had one main crossing, a ford, where the village of Kafir-ul-Ma stands today. 
In most Muslim accounts the size of the united forces was stated between 24,000 and 40,000 and the number of Byzantine forces at between 100,000 and 200,000. Size of Byzantine army is highly exaggrated. Modern estimates of the sizes of the respective armies vary: between 80,000 - 120,000, some estimates as lowe as 50,000. Estimates for Rashidun army are between 25,000 - 40,000. These figures come from studying the logistical capabilities of the combatants, the sustainability of their respective bases of operations, and the overall manpower constraints affecting the Romans and Arabs. Most scholars, however, agree that the Byzantine army and their allies outnumbered the Muslim Arabs by a sizeable margin.
The army was lined up on a front of ten miles, with its left on the Yarmouk River a mile before the ravine began and its right on the Jabiya road, with substantial gaps between the divisions so that they could cover the whole area that Byzantines were covering with there 11 miles battle front. The Yarmouk River ( Arabic: نهر اليرموك, " Nahr Al-Yarmuk " Hebrew: נהר הירמוך " Nehar HaYarmukh " The center of the army was under the command of Abu Ubaidah ibn al-Jarrah (left half) and Shurhabil bin Hassana (right half). The left wing was under the command of Yazid and the right wing was under Amr ibn al-A'as. Center, left and right wings were given cavalry regiments under command, to be used as a reserve for counter attack in case they were pushed back by the Byzantines. A counterattack Behind the center stood mobile guard under the personal command of Khalid. When Khalid was occupied in the conduct of the battle, Zirrar ibn al-Azwar would command the mobile guard. Each of the four corps had nine infantry regiments, which were all formed on a tribal and clan basis, so that every man would fight next to well-known comrades, and the army pushed out a line of scouts to keep the Byzantines under observation. The Infantry is the oldest and most numerous of the Combat Arms in the Armed forces, and consists  The battle formation of Tabi'a was used which was a type of close defensive formation. During a council of war, Khalid ibn Walid, the former commander in chief of the Rashidun army in the campaign of Syria, offered his services as a commander of the Muslim army until the battle was over and it was given to him that day; Abu Ubaidah ibn al-Jarrah's military credentials were not as high as Khalid's. The Rashidun Caliphate Army or Rashidun army was the primary military body of the Rashidun Caliphate 's Armed forces during the Muslim Syria ( سوريّة or) officially the Syrian Arab Republic (Arabic ar الجمهورية العربية السورية  After taking command, Khalid reorganized the army into infantry and cavalry regiments, with cavalry making up a quarter of army. Khalid further divided the army into 36 infantry regiments and four cavalry regiments; with his cavalry elite, mobile guard, held in reserve. The Mobile guard ( متحرك طليعة), was a Light cavalry of Rashidun army during the Muslim conquest of Syria, that remained under the Over the course of the battle Khalid would repeatedly make critical, decisive use of this mounted reserve. In late July 636, Mahan sent Jabla with his Christian Arabs forces to check the strength of the Muslim front, but they were repulsed by the mobile guard under Khalid.  After this initial operation, no military activities occurred for a month.
The helmets included gilded helmets similar to that of silver helmets of Sassanid empire. Mail was commonly used to protect the face, neck and cheek either as an aventail from the helmet or as a mail coif. Heavy leather sandals as well as Roman type sandal boots were also typical of the early Muslim soldiers. Armor included, Hardened leather scale or lamellar armour, mail armors. Lamellar Armour is a kind of personal armour consisting of small plates ( lames) which are laced together in parallel rows Mail (also maille, often given as chain mail or chain maille) is a type of Armour or jewellery that consists of small metal rings linked Infantry soldiers were more heavily armored then the horsemen. Hauberks and large wooden or wickerwork shields were used. A hauberk is a shirt of mail Armour. The term is usually used to describe a shirt reaching at least to mid-thigh and including sleeves Wicker is hard woven Fiber formed into a useful object Wicker is usually used for Baskets or Furniture. A shield is a protective device meant to intercept attacks The term often refers to a device that is held in the hand as opposed to Armour or a Bullet proof vest Long-shafted spears were used. Infantry spears were two and a half meter long and that of cavalry were up to five and a half meters long. In swords, a short infantry weapon like that of Roman gladius and Sassanid long swords were bring used. Gladius is a Latin word for Sword. Early ancient Roman swords were similar to those used by the Greeks Swords were hanged in baldric. A baldric (also baldrick, bawdrick, bauldrick as well as some other mostly rare or obsolete variations is a belt worn over one Shoulder Bows were about two meter long when unbraced, about the same size of famous english longbow. The maximum useful range of the traditional Arabian bow use to be about 150 meters. Early Muslim archers were infantry archers who proved to be very effective against the cavalry.
A few days after Muslims, the Byzantine army — proceeded by the lightly armed Ghassanids of Jabla — moved forward and established their strongly fortified camps just north of the Wadi-ur-Raqqad, some Byzanitne sources also mentions a fortified encampment at Yaqusah, 18 kilometer from the battlefield.  Vahan deployed the Imperial Army forward of Allan, with a front about 11 miles long, as he was trying to cover the whole area between Yarmouk gorge and Roman road to Egypt, and there have been substantial gaps between the byzantine division. This article is about the country of Egypt For a topic outline on this subject see List of basic Egypt topics. He used his four regular armies to form the line of battle, extending from the Wadi Allan to south of the Hill of Jabiya. The right wing was commanded by Gregory and left was commanded by Qanateer. The centre was formed by the army of Dairjan and the Armenian army of Mahan-both under the command of Dairjan. The Roman regular cavalry was distributed equally among the four armies, with each army deployed with its infantry holding the front and its cavalry held as a reserve in the rear. Ahead of the front line, across the entire 11-mile front, Vahan deployed the Christian Arab army of Jabla, which was all mounted on horses and camels. This army acted as a screen and skirmish line, until they would be joined by the main army. Skirmishers are Infantry or Cavalry Soldiers stationed ahead or alongside of a larger body of friendly troops The army of Gregory, which formed the right wing, used chains to link its foot soldiers together.  All these foot soldiers had taken the oath of death. These chains were in 10-men lengths, and were used as a proof of unshakeable courage on the part of the men, who thus displayed their willingness to die where they stood and not retreat. The chains also acted as an insurance against a break-through by enemy cavalry, however modern historians suggest that Byzantines adopted the Greko-Roman military formation known as the testudo formation in which soldiers would stand shoulder-to-shoulder with shields held high and a 10-20 men arrangement would be completely shielded on all sides with the next soldier providing defence for the other. In Ancient Roman Warfare the testudo or tortoise formation was a formation used commonly by the Roman Legions during battles particularly sieges
Byzantine cavalry was armed with long swords known as Spathion. They would also have a light wooden lance known as kontarionand a bow (toxarion) with 40 arrows in it quiver, hung from a saddle or from belt. The term lance has become a catchall for a variety of different Pole weapons based on the Spear. Heavy infantry, known as Skoutatoi had a short sword and a short spear. Light byzantine troops, the archer, carried a small shield, a bow across the back hung from the shoulder rather then a belt and a quiver full with arrows. Cavalry armour consist of mail hauberk with a mail coif, and a helmet with a pendant i. Mail, or post, is a method for transmitting information and tangible objects wherein written Documents typically enclosed in Envelopes and also Mail, or post, is a method for transmitting information and tangible objects wherein written Documents typically enclosed in Envelopes and also A coif (ˈkɔɪf is a close fitting cap that covers the top back and sides of the head worn by all classes in England and Scotland from the e a throat guard lined with a fabric and having a fringe and with a check piece. The infantry similarly had a mail hauberk and helmets and leg defences. Where as light lamellar and scale armour was also used. A lamella is a Gill -shaped structure fine sheets of material held adjacent one another with fluid in-between-(or simply 'welded'-plates Scale armour (armor, Lorica squamata, lorica plumata consists of many small scales attached to a backing material of either leather or Cloth. 
It was a rare occasion of Byzantines engaging in decisive battle and it created logistical constraints on Byzantines, Rashisdun army's strategy of withdrawl from all occupied areas and concentrating all troops at one place to give a decisive battle inturn forced all five of the Byzantine armies to concentrate at one place. This created logistic problems for the Byzantines as Damascus was only closest logistic base and Mansur, leader of Damascus, couldn’t supply massive Byzantine army that was gathered at yarmouk plain and few clashes were reported with local citizens over supply requisition, as it was end of summer and thus decline of pasturage. Greek court sources also claim treasonous disobedience to Heraclius’ command not to engage in large-scale battle with Arabs, but after concentration of Muslims at yarmouk, Vahan had no other option available. The relation between byzantine commander were also not less tense, and there was a struggle for power between Trithurios and Vahan, Jarajis and Qanatir (Buccinator). Jabla, the Christian Arab leader was ignored several time, though his opinion was of great importance as the region was of his domain and he had a good knowledge of the terrain. Thus a mistrust was created between Greeks, Armenians, and Arabs. Ecclesiastical feuds between Monophysite and Chalcedon are reported though it didn't had any direct impact, but underlyed tensions. All this decreased coordination and planning, one of the reason of Byzantine catastrophic defeat in the battle. 
Vahan was instructed by Heraculis, not to start battle until all avenues of peaceful negotiation had been explored. Grogory and then Jabla were sent by Vahan to negotiate but their efforts failed. Before the battle, on Vahan’s invitation, Khalid came to talks but still with no result.  Meanwhile Caliph Umar sent a reinforcement of 6,000 troops, mostly from Yemen as well as 1,000 Sahaba (companions of Muhammad), among them a 100 veterans of the Battle of Badr, the first battle of Islamic conquest. The army also included citizens of the highest rank, such as Zubair, Abu Sufyan, and his wife Hind bint Utbah. For the son of Harith see Abu Sufyan ibn al-Harith. Sakhr ibn Harb (صخر بن حرب more commonly known as Abu Sufyan (560-650 Hind bint Utbah (هند بنت عتبة was an Arabic woman who lived in the late 6th and early 7th centuries CE she was the wife of Abu Sufyan ibn Harb, a  Thus Byzantines were forced to attack because the Muslims kept getting reinforcements. 
The battle started on 15 August 636 At dawn both armies lined up for battle and were a little less than a mile apart. Events 778 - The Battle of Roncevaux Pass, at which Roland is killed Events By Place Byzantine Empire August 20 — Battle of Yarmuk: Khalid ibn al-Walid 's victory against the  Before the battle would commence, George rode up to the Muslim end and converted to Islam, secretly vowing to support the enemy. The battle began with regular skirmishing and fights between champions. Skirmishers are Infantry or Cavalry Soldiers stationed ahead or alongside of a larger body of friendly troops At midday, Vahan attempted a limited offensive through the Byzantine infantry to test the strength and strategy of the Muslim army, and if possible, achieve a breakthrough wherever the Muslim front was weak. On some parts of the front the fighting was intense, but on the whole the action of this day could be described as steady and moderately hard.  The Muslims held their own. The Byzantine forces did not reinforce their forward infantry, and at sunset the action ended with the two armies separating and returning to their respective camps. The Infantry is the oldest and most numerous of the Combat Arms in the Armed forces, and consists 
On 16 August 636, Vahan in a council of war decided to launch his attack just before dawn, to catch Muslims unprepared at the time of morning prayers. Events 1384 - The Hongwu Emperor of Ming China, Emperor Dong hears a case of a couple who tore paper money bills while fighting Events By Place Byzantine Empire August 20 — Battle of Yarmuk: Khalid ibn al-Walid 's victory against the He planned to engage the two of his central armies with the Muslim centre to stall them while the main thrusts would be against the wings of the Muslim army, which would then be either be driven away from the battlefield or pushed towards the centre. To observe the battlefield Vahan had a large pavilion built behind his right wing with an Armenian bodyguard force. He ordered the army to prepare for the surprise attack. 
Unknowingly to the Byzatines, Khalid had placed a strong outpost line in front during night to counter surprises, which gave the Muslims time to prepare for battle.  At the center, the Byzantines did not press hard, as this was meant to be a limited attack to pin the Muslim central corps in their position.  Thus the center remained stable. But on the left wing of the Byzantine army, the Qanateer, commanding a force of mainly Slavs, attacked and forced the Muslim infantry to retreat. Amr, the Muslim right wing commander ordered his cavalry regiment to counter attack, which checked the Byzantine advance and stabilized the battle line on the right for some time. Khalid aware of the situation at the wings, ordered his mobile guard and the reserve cavalry on the right to assist the right wing infantry. The Slavs attacked from both sides by Muslim cavalry retreated to their original position and Amr regained all the ground he had lost while starting to reorganise his corps for another round.
The situation on the Muslim left wing where Yazid commanded was slightly serious. Whilst the Muslim right wing enjoyed assistance from the mobile guard, the left wing were retreating back to their camps. Here the Byzantines had broken through the corps. The testudo formation that Gregory's army had adopted moved slow but also had a good defence. In Ancient Roman Warfare the testudo or tortoise formation was a formation used commonly by the Roman Legions during battles particularly sieges Yazid used his cavalry regiment to counter attack but was repulsed. After a period of stiff resistance the warriors of Yazid finally fell back to their camps and for a moment Vahan's plan appeared to be succeeding. The centre of the Muslim army was pinned down and its flanks had been pushed back. Although being forced back, neither flank had broken only their morales were severly beaten.  The retreating Muslim amry, however, were met by the ferocious Arab women at the camps. Led by Hind, the Muslim women dismantled their tents and armed with tent poles and charged at their husbands and fellow men signing an improvised song that Hind had also sung at the Battle of Uhud. The Battle of Uhud (غزوة أحد) was fought on 23 March 625 (3 Shawwal 3 AH in the Islamic calendar) at Mount Uhud, in what
“O you who run from a constant woman
Who has both beauty and virtue;
And leave her to the infidel,
The hated and evil infidel,
To possess, disgrace and ruin. ”
This boiled the blood of the retreating Muslims further and they fled back into the battlefield. 
With the position on the right stabilised, the mobile guard cavalry moved towards the left wing. Khalid detached one regiment under Zirrar ibn al-Azwar and ordered him to attack the front of the army of Deirjan(left half of the center) in order to create a diversion and threaten the withdrawal of the Roman right wing from its advanced position. A regiment is a Military unit, composed of a variable number of Battalions – commanded by a Colonel. With the rest of the cavalry reserve he attacked the flank of Gregory. Here again, under simultaneous attacks from the front and flank, the Byzantines fell back, but more slowly because assuming their formation the men could not move as fast.  At sunset the central armies broke contact and withdrew to their original positions and both fronts were restored along the lines occupied in the morning. The death of Dairjan and the failure of Vahan's battle plan left the Imperial army relatively demoralized, whereas Khalid's successful counter-attacks emboldened his troops. 
On 17 August 636, Vahan pondered over his failures and mistakes of the previous day. Events 986 - A Byzantine army was destroyed in the pass of Trajan's Gate by the Bulgarians under the Comitopuli Events By Place Byzantine Empire August 20 — Battle of Yarmuk: Khalid ibn al-Walid 's victory against the What bothered him the most was the loss of one of his commanders. The imperial Byzantine army decided on a less ambitious plan, aiming to break the Muslim army at a specific points.  The battle resumed with the Byzantine attack. After holding the initial attacks by the Byzantines, the Muslim right retreated toward their base camp followed by the retreat of the right half of the Muslim center. , but the corps were able to reorganize some distance from the camp for a counter-attack.  Knowing instantly that the Byzantine army was focusing on the Muslim right, Khalid launched an attack with his mobile guard, alongwith the Muslims right's cavalry, on the other end of the Byzantines where Qanateer commanded. The combat soon accelerated into a bloodbath. Many fell on both sides and by dusk the Byzantines had been pushed back to their former positions and the situation restored to that existing at the beginning of the battle. 
18 August 636, the fourth day was to prove decisive. Events 293 BC - The oldest known Roman temple to Venus is founded starting the institution of Vinalia Rustica. Events By Place Byzantine Empire August 20 — Battle of Yarmuk: Khalid ibn al-Walid 's victory against the Vahan decided to persist with the previous day's war plan as he had been successful in inflicting damage on the Muslim right. Qanateer led two armies of Slavs against the Muslim right and right half of centre with a little assistance from the Armenianas and Christian Arabs led by Jabala. The Muslim armies were forced back but held position at the right wing with the Slavs while the right half of the Muslim centre gave way after repetitive attacks by the Armenians and Christian Arabs soldiers under Jabala. While the Muslim right was preoccupied, Khalid entered the fray yet again with this mobile guard. He feared a general attack on a broad front which would make it impossible for him to repulse and as a precaution ordered Abu Ubaida and Yazid on the left centre and the left wings respectively to attack the Byzantine armies at the respective fronts. The attack would result in stalling the Byzantine front and preempt a general advance of the Imperial army.  With his mobile guard, Khalid struck the advancing Armenians. He divided his mobile guard into two equal groups of which one would attack at the Armenians at the front, while leading his own cavalry group, Khalid galloped round behind the fighting Muslim army appeared against the Armenians at their front. This three-pronged flanking manoeuvre against the Armenians and Christian Arabs with extreme cavalry-enabled force led the Armenians to retreat towards their original position. In Military tactics, a flanking maneuver, also called a flank attack, is an attack on the sides of an opposing force The Slavs were left alone in the battlefield without the Armenian support and soon retired as well. Shurahbil's and Amr's positions were secured.
While Khalid and his mobile guard were busy with this end of the battle throughout the afternoon, situation on the other end was worsening. Byzantine horse-archers had taken into the battlefield and had prevented Abu Ubaidah and Yazid from penetrating into their lines. Many Muslim soldiers lost their sight to Byzantine arrows on that day, which thereafter became known as the "Day of Lost Eyes".  The veteran Abu Sufyan also lost one eye. For the son of Harith see Abu Sufyan ibn al-Harith. Sakhr ibn Harb (صخر بن حرب more commonly known as Abu Sufyan (560-650 The Muslim armies fell back except for one regiment led by Ikramah bin Abu Jahal, which was on the left of Abu Ubaidah's corps. Ikramah had called on his men to take an oath of death and to go down fighting without retreat. While these four hundred men attacked the Byzantine front, the other armies reorganised themselves to counter-attack and gain their lost positions. All of Ikramah's men were either seriously injured or died that day. Ikrimah and his son Amr, a childhood friend of Khalid's were mortally wounded and died later in the evening. 
Early on 19 August 636, the fifth day of battle Vahan sent an emissary to the Muslim camp for a truce for the next few days so that fresh negotiations could be held. Events 43 BC - Octavian, later known as Augustus compels the Roman Senate to elect him Consul. Events By Place Byzantine Empire August 20 — Battle of Yarmuk: Khalid ibn al-Walid 's victory against the Abu Ubaidah nearly accepted the proposal but was restrained by Khalid. Khalid had been terribly sad at the death of his friend the earlier day and gave in to him emotions while also devising a clear-cut offensive strategy. On Khalid's insistence he sent the envoy back with a negative reply, adding:
We are in a hurry to finish this business!
Khalid knew that the Byzantines were no longer eager for battle. Up until now the Muslim army had adopted a largely defensive strategy, but Khalid now decided to take the offensive and reorganized his troops accordingly. All the cavalry regiments were grouped together into one powerful mounted force with the mobile guard acting as its hard core. The Mobile guard ( متحرك طليعة), was a Light cavalry of Rashidun army during the Muslim conquest of Syria, that remained under the The total strength of this cavalry group was now about 8,000 mounted warriors, an effective corps for an offensive attack the next day. The rest of the day passed uneventful.
On 20 August 636, the final day of battle, Khalid formulated a simple but bold plan of attack and immediately put it into action. Events 636 - Battle of Yarmouk: Arab forces led by Khalid ibn al-Walid take control of Syria and Palestine Events By Place Byzantine Empire August 20 — Battle of Yarmuk: Khalid ibn al-Walid 's victory against the With his massed cavalry force he intended to drive the Byzantine cavalry entirely off the battlefield so that the infantry, which formed the bulk of the imperial army, would be left without cavalry support and thus be exposed and helpless when attacked from the flanks and rear. At the same time he planned to push a determined attack to turn the left flank of the Byzantine army and push them toward the ravine to the west.
While the Muslim centre and left wing engaged the Byzantine armies on their fronts to pin them down, Khalid deployed his cavalry and charged the Byzantine left flank. At the same time he also dispatched a mounted regiment to engage and pin down the Byzantine cavalry on the left. The infantry was then engaged into battle simultaneously with the cavalries.
The Slavic infantry under Qanateer resisted the attack but without support from their cavalry they fell back and retreated towards the Armenian armies of Vahan. The Muslim armies focused entirely on dibanding them the same way they did the Slavs. Vahan noticing the huge cavalry formation the Muslim ordered his cavalry to come together and counter-attack the advancing massed Muslims but was not quick enough; before Vahan could organize his disparate heavy cavalry squadrons, Khalid had galloped his cavalry back to attack the concentrating Byzantine horses, falling upon them from the front and the flank while they were still manoeuvring into formation. Heavy cavalry is the late 19th century Misnomer for Cavalry troops that from the late 17th to late 19th centuries usually wore armour and were mounted on largest The Muslim horsemen were lightly armed and fast versus the disorganized and disoriented Byzantine cavalry that soon broke contact and dispersed to the north, leaving the infantry to its fate. With the cavalry retreating towards the north including the mounted corps of Jabala, the infantry lay unguarded and Khalid now turned his focus onto them attacking the Armenian army of Vahan from the rear. The Armenians were strong fighters but without support from Jabala reserve light infantry their line broke and they fell back.
As the Armenians retreated, it was the unit of Trithyrius that accepted Khalid's mighty blows and soon the entire Byzantine army was in full retreat. Part scattered in panic and others fell back in good order to the west towards Wadi Ruqqad.  Khalid now turned this retreat into a rout, taking his cavalry towards the north-west so that no troops could escape from there, though before he could seal off all the gaps, a few thousand Byzantine troops escaped towards Damascus by way of a bridge at 'Ayn Dhakar over the deep gorges of the ravines of Wadi Ruqqad. In the confusion of the rout, Zarrar had already captured the bridge as part of Khalid's plan the night before. A unit of 500 mounted troops were sent through to block this passageway. In fact, this was the route Khalid wanted the Byzantines to retreat along all the time. The Byzantines were surrounded from all ends now.  Some fell into the 200-meters deep ravines off the steep slopes, some tried jumping into the water only to be smashed on the rocks below and some were killed while fighting. The remaining put their hands down and surrendered but the Muslims were unforgiving and they administered a massacre taking very few prisoners. 
Immediately after this operation was over, Khalid and his mobile guard moved north to pursue the retreating Byzantine soldiers; he found them near Damascus and attacked. Damascus ( دمشق,, also commonly known as الشام ash-Shām) is the capital and largest city of Syria. In the ensuing fight the commander-in-chief of the imperial army, the Armenian prince Vahan who had escaped the fate of most of his men at Yarmouk, was killed. Khalid then entered Damascus where he was welcomed by the local residents, thus recapturing the city. 
When news of the disaster reached the Byzantine Emperor Heraclius at Antioch, he was devastated and enraged.  He blamed his wrongdoings for the loss primarily referring to his incestuous marriage to his niece Martina.  He would have tried to win over the province if he had the resources, rather he resorted to the cathedral of Antioch where he observed a solemn service of intercession. This article is about the history and organisation of the cathedral Distinguish from "inter-session" ie "between Sessions " Intercession, in both Christianity and Islam,  He summoned a meeting of his advisers at the cathedral and scrutinized the situation. He was told almost unanimously and accepted the fact the defeat was God's decision and a result of the sins of the people of the land including him.  Heraclius took to the sea on a ship to Constantinople in the night. 
It is said that as his ship was set sail, he bade a last farewell to Syria, saying:
Haraclius abandoned Syria with the holy relic of the True Cross on-board, not just to protect it from the invading Arabs but also for his own protection at sea. The True Cross is the name for physical remnants which by a Christian tradition are believed to be from the actual cross upon which Jesus was crucified It is said that the emperor had a fear of water.  After abandoning Syria, the Emperor began to concentrate on his remaining forces for the defence of Egypt instead. This article is about the country of Egypt For a topic outline on this subject see List of basic Egypt topics. The Byzantines again were defeated by the Muslims led by Amr ibn al-A'as — who had commanded the right flank of the Rashidun army at Yarmouk. ˤAmr ibn al-ˤĀs (عمرو بن العاص (born c583 - d January 6, 664 CE was an Arab Military commander who is most noted for leading
The Battle of Yarmouk can be seen as an example in military history where an inferior force manages by superior generalship to overcome a superior one. Military history is a Humanities discipline within the scope of general historical recording of armed conflict in the history of humanity
The Imperial Byzantine commanders allowed their enemy to have the battlefield of his choosing. Even then they were at no critical tactical disadvantage. Khalid knew all along that he was up against a force superior in numbers and, until the last day of the battle, he conducted an essentially defensive campaign suited to his relatively limited resources. When he decided to take the offensive and attack on the final day of battle, he did so with a degree of imagination, foresight and courage that none of the Byzantine commanders ever displayed. Although he commanded a numerically inferior force and needed all the men he could muster, he nevertheless had the confidence and foresight to dispatch a cavalry regiment the night before his assault to seal off a critical path of retreat for the enemy army. Khalid ibn al-Walid was one of the finest cavalry commanders in history, and his use of mounted warriors throughout the battle showed just how well he understood the potentials and strengths of mounted troops. Khālid ibn al-Walīd (592-642 ( خالد بن الوليد) also known by Sunnis as Sayf-'ullah al-Maslul (the Drawn Sword of God, God's Withdrawn His mobile guard moved quickly from one point to another, always changing the course of events wherever they appeared, and then just as quickly galloping away to change the course of events elsewhere on the field. The Mobile guard ( متحرك طليعة), was a Light cavalry of Rashidun army during the Muslim conquest of Syria, that remained under the
Mahan and his Byzantine commanders never dealt with this mounted force effectively. Their own Byzantine cavalry never played a significant role in the battle and were held in static reserve for most of the six days. They never pushed their attacks and even when they obtained what could have been a decisive breakthrough on the fourth day, they were unable to exploit it. There appeared to be a decided lack of resolve among the Imperial commanders, though this may have been caused by difficulties commanding the army because of internal conflict. Moreover, many of the Arab auxiliaries were mere levies, while the Muslim Arab army consisted for a much larger part of veteran troops.
The original strategy of Heraclius, to destroy the Muslim troops in Syria piecemeal, needed rapid and quick deployment to be implemented, but the commanders on the ground never displayed these qualities. Ironically, on the field at Yarmouk, Khalid carried out on a small tactical scale what Heraclius had planned on a grand strategic scale: by rapidly deploying and manoeuvering his forces, Khalid was able to temporarily concentrate sufficient forces at specific locations on the field to defeat the Byzantine troops in detail. Mahan was never able to make his numerical superiority count, partly because of the unfavorable terrain that prevented large-scale deployment. However, at no point did Mahan attempt to concentrate a superior force to achieve a critical breakthrough. Although he was on the offensive 5 days out of the six, his battle line remained remarkably static. This all stands in stark contrast to the very successful offensive plan that Khalid carried out on the final day, when he reorganised virtually all his cavalry and committed them to a grand maneouvre that won the battle. 
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