Cymbeline had voluntarily paid tribute to Rome, but Guiderius refused to pay it.
Claudius and his chief of staff, Lelius Hamo, landed at Portchester, entrenching themselves there while besieging the city.
Guiderius conscripted all the men of Britain against Claudius and marched south to meet him in battle.
[2] Hamo, though, put on British armour and began attacking his own army, urging the Britons to do likewise.
He and his brother Arvirargus had been kidnapped in childhood by Belarius, a nobleman wrongly banished by Cymbeline, and brought up in secret in Wales, but are reunited with their father and sister Imogen in time for the Roman invasion.