After four years of erratic and increasingly tyrannical rule, Caligula was ambushed by Praetorian Guard officers, led by Cassius Chaerea, a tribune he had repeatedly mocked. The assassination plunged the palace into chaos, and his uncle Claudius, discovered hiding behind a curtain by a soldier, was declared the next emperor almost by accident.
Caligula had humiliated Cassius Chaerea for years, mocking his voice and giving him obscene watchwords as a running joke about his masculinity. On January 24, as the emperor left a theatrical performance and walked through a narrow palace passage, Chaerea and fellow guardsmen struck, stabbing him more than thirty times.
The murder was not a clean political transition but a spasm of violence — soldiers went on to kill Caligula's wife Caesonia and dash his infant daughter's head against a wall, fearing any surviving heir. Amid the pandemonium, a soldier searching the palace found Claudius, Caligula's uncle, trembling behind a curtain, and rather than killing him, hailed him as emperor.
The episode remains one of antiquity's starkest lessons in the fragility of absolute power: a ruler who believed himself a living god was undone by a bodyguard he had turned into a joke.
Key people: Caligula, Cassius Chaerea