In 52 BC the Atrebates joined the pan-Gaulish revolt led by
Vercingetorix, and Commius was one of the leaders of the army that attempted to relieve Vercingetorix at the
Siege of Alesia. After Vercingetorix was defeated Commius joined a revolt by the
Bellovaci and persuaded some 500 Germans to support them, but this too was defeated and Commius sought refuge with his German allies. In 51 BC he returned to his homeland with a small mounted war-band for a campaign of agitation and
guerrilla warfare. That winter
Mark Antony, a legionary legate at the time, ordered Volusenus to pursue him with cavalry, something Volusenus was more than happy to do. When the two groups of horsemen met Volusenus was victorious, but sustained a spear-wound to the thigh. Commius escaped and sued for peace through intermediaries. He offered hostages and promised he would live where he was told and no longer resist Caesar, on the condition that he never again had to meet a Roman. Antony granted his petition. A 1st century AD source,
Sextus Julius Frontinus's
Strategemata, tells how Commius fled to Britain with a group of followers with Caesar in pursuit. When he reached the
English Channel the wind was in his favour but the tide was out, leaving the ships stranded on the flats. Commius ordered the sails raised anyway. Caesar, following from a distance, assumed they were afloat and called off the pursuit. This suggests that the truce negotiated with Antony broke down and hostilities resumed between Commius and Caesar. However John Creighton suggests that Commius was sent to Britain as a condition of his truce with Antony - where better to ensure that he never again met a Roman? - and that Frontinus's anecdote either refers to an escape prior to the truce, or is historically unreliable, perhaps a legend Frontinus heard while
governor of Britain (75 to 78 AD). Creighton argues that Commius was in fact set up as a friendly king in Britain by Caesar, and his reputation was rehabilitated by blaming his betrayal on Labienus (who deserted Caesar for
Pompey in the
civil war of 49 - 45 BC). Commius's name appears on coins of post-conquest date in Gaul, paired with either
Garmanos or
Carsicios. This suggests he continued to have some power in Gaul in his absence, perhaps ruling through
regents. Alternatively, Garmanos and Carsicios may have been Commius's sons who noted their father's name on their own coins. ==King in Britain==