After conquering Gaul, Julius Caesar sets his sights on Britain, though he does not want to destroy the Britons since he regards them as fellow descendants of Trojan royalty. Caesar sends a letter to Cassivelaunus demanding that he pay tax to Rome. In his response, Cassivelaunus chastises Caesar for attempting to subjugate a Trojan kinsman and asserts that Britain will fight to defend its freedom. Caesar attacks. Cassivelaunus gathers his princes and advisors, who put up a spirited defense. Cassivelaunus’ brother Nennius battles Caesar, capturing his sword, but is eventually mortally wounded. Defeated, Caesar returns to Gaul with his troops. Inspired, the Gauls rebel, but Caesar buys off local chieftains, promises slaves their freedom and to restore to the disinherited “their lost possessions,” and thus retains his power (92).

Two years later, Caesar prepares a second assault of Britain. Despite displaying bravery, the Romans lose again. Caesar flees with his troops, and they retreat to the open sea while Cassivelaunus celebrates his second victory with sacrifices, feasts, and sporting events. During the celebration, a quarrel occurs between the king’s nephew, Hirelgdas, and the Duke of Androgeus’ nephew, Cuelinus. Cuelinus cuts off Hirelgdas’ head. Upset by his nephew’s murder, Cassivelaunus demands that Androgeus bring Cuelinus before him, but Androgeus refuses.