Mandubracius or Mandubratius was a king of the Trinovantes of south-eastern Britain in the 1st century BC. The Trinovantes or Trinobantes were one of the Celtic Tribes that lived in pre- Roman Britain. Prehistoric Britain was a period in the human occupation of Great Britain that was the later part of Prehistory, conventionally ending with the Roman invasion The 1st century BC started the first day of 100 BC and ended the last day of 1 BC.
Mandubracius was the son of a Trinovantian king, named Imanuentius in some manuscripts of Julius Caesar's De Bello Gallico, who was overthrown and killed by the warlord Cassivellaunus some time before Caesar's second expedition to Britain in 54 BC. Imanuentius appears in some manuscripts of Julius Caesar 's De Bello Gallico as the name of a king of the Trinovantes, the leading nation of south-eastern Commentarii de Bello Gallico is Julius Caesar 's third-person account of his nine years of war in Gaul. Cassivellaunus was a historical British chieftain who led the defence against Julius Caesar 's second expedition to Britain in 54 BC. During his Gallic Wars, Julius Caesar invaded' Britain twice in 55 and 54 BC. Year 54 BC was a year of the pre-Julian calendar. Events By place Rome Consuls Appius Claudius Pulcher and Mandubracius fled to the protection of Caesar in Gaul. Cassivellaunus then led the British defence against the Romans, but the Trinovantes betrayed the location of his fortress to Caesar, who proceeded to besiege him there. Ancient Rome was a Civilization that grew out of a small agricultural community founded on the Italian Peninsula as early as the 10th century BC As part of the terms of Cassivellaunus's surrender, Mandubracius was installed as king of the Trinovantes, and Cassivellaunus undertook not to make war against him. 
He appears in Geoffrey of Monmouth's Historia Regum Britanniae (1136) as Androgeus, eldest son of the legendary king Lud. Geoffrey of Monmouth ( Gruffudd ap Arthur or Sieffre o Fynwy) (c The Historia Regum Britanniae ( English: The History of the Kings of Britain) is a pseudohistorical account of British history Lud, according to Geoffrey of Monmouth 's legendary History of the Kings of Britain and related medieval texts was a king of Britain in pre- The name change can be traced to copying errors in Orosius's Seven Books of History Against the Pagans, a 5th century Christian history which was influential in medieval Britain, where it appears in different manuscripts as "Mandubragius" and "Andragorius". Paulus Orosius (b circa 375 d 418? was a Christian Historian, theologian and disciple of St  Bede, who follows Orosius almost verbatim for his account of Caesar's expeditions, calls him "Andragius" (a name which Geoffrey used for an earlier British king). Bede (ˈbiːd (also Saint Bede, the Venerable Bede, or (from Latin Beda (beda (c Andragius was a legendary king of the Britons as accounted by Geoffrey of Monmouth. Geoffrey may also have been influenced by the Greek mythological character Androgeus. Greek mythology is the body of stories belonging to the ancient Greeks concerning their gods and Heroes the nature of the world and the origins and significance For Androgeus legendary King of the Britons see Androgeus of Britain.
When Lud died, Androgeus and his brother Tenvantius were too young to rule, so the throne went to their uncle Cassibelanus. Tasciovanus was a historical king of the Catuvellauni tribe before the Roman conquest of Britain. Cassivellaunus was a historical British chieftain who led the defence against Julius Caesar 's second expedition to Britain in 54 BC. Androgeus was made Duke of Trinovantum (London) and Kent, and participated in the defence of Britain against Julius Caesar. Trinovantum, in medieval British legend is the name given to London in earliest times London ( ˈlʌndən is the capital and largest urban area in the United Kingdom. KENT (1400 AM) is a Radio station broadcasting a Adult Standards/MOR format After Caesar's first two invasions were repelled, the Britons held a celebration at which sacrifices were made to the gods and games played. Cuelinus, a nephew of Androgeus, wrestled with Hirelglas, Cassibelanus's nephew, and killed him in a dispute over the result. Cassibelanus demanded Androgeus hand over his nephew for trial, but fearing the king's intentions, Androgeus refused, offering to try him in his own court. Cassibelanus made war on Androgeus, who appealed to Caesar for help. He gave hostages, including his own son Scaeva, as proof of his intentions, and Caesar invaded a third time. Between them, Androgeus and Caesar forced Cassibelanus to submit and agree to pay tribute to Rome. Caesar spent the winter in Britain, and he and Cassibelanus became friends. When he finally returned to Rome to fight the civil war against Pompey, Androgeus went with him, never to return. The Roman civil war of 49 BC sometimes called Caesar's Civil War, is one of the last conflicts within the Roman Republic. Gnaeus Pompeius Magnus, commonly known as Pompey /'pɑmpi/ Pompey the Great or Pompey the Triumvir ( Classical Latin abbreviation 
In Middle Welsh versions of Geoffrey's Historia, and in the Welsh Triads, he appears as Afarwy. Middle Welsh (Cymraeg Canol is the label attached to the Welsh language of the 12th to 14th centuries of which much more remains than for any earlier The Welsh Triads ( Welsh Trioedd Ynys Prydein, literally "Triads of the Island of Britain " are a group of related texts in Medieval The Triads name him as one of the "Three Dishonoured Men of the Island of Britain" for inviting Caesar to invade. 
John Koch suggests that Mandubracius may be the historical basis of the Welsh mythological figure Manawydan: he reconstructs the original form of his father's name as *Mannue:tios, and an earlier form of Manwydan as *Mannue:tiagnos, "son of Mannuetios". Welsh mythology, the remnants of the Mythology of the pre Christian Britons, has come down to us in much altered form in medieval Welsh manuscripts In Welsh mythology, Manawydan, son of Llyr, is the equivalent of the Irish Manannan mac Lir and a presumed sea god.