Cassivellaunus

Cassivellaunus was a historical British tribal chief who led the defence against Julius Caesar's second expedition to Britain in 54 BC. He led an alliance of tribes against Roman forces, but eventually surrendered after his location was revealed to Julius Caesar by defeated Britons.

Cassivellaunus made an impact on the British consciousness. He appears in British legend as Cassibelanus, one of Geoffrey of Monmouth's kings of Britain, and in the Mabinogion, the Brut y Brenhinedd and the Welsh Triads as Caswallawn, son of Beli Mawr. His name in Common Brittonic, *Cassiuellaunos, comes from Proto-Celtic *kassi- "passion, love, hate" (alternately, "long hair", or "bronze") + *uelna-mon- "leader, sovereign".

Cassivellaunus appears in Julius Caesar's Commentarii de Bello Gallico, having been given command of the combined British forces opposing Caesar's second invasion of Britain. Caesar does not mention Cassivellaunus's tribe, but his territory, north of the River Thames, corresponds with that inhabited by the tribe named the Catuvellauni at the time of the later invasion under Claudius.

Caesar tells us that Cassivellaunus had previously been in near-constant conflict with his neighbors, as was typical of the British tribes in this period, and had recently brought down the king of the Trinovantes, the most powerful tribe in Britain at the time. The king's son, Mandubracius, fled to Caesar in Gaul. Despite Cassivellaunus's harrying tactics, designed to prevent Caesar's army from foraging and plundering for food, Caesar advanced to the Thames. The only fordable point was defended and fortified with sharp stakes, but the Romans managed to cross it. Cassivellaunus dismissed most of his army and resorted to guerilla tactics, relying on his knowledge of the territory and the speed of his chariots.

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