プラエトリアニ
When the Emperor tries to have Demetrius executed, the Praetorian Guard (already angry at Caligula over worse pay and conditions) finally turns against Caligula and kills first Macro, the prefect of the Praetorian Guard, and then Caligula himself. Claudius is installed as Emperor by the Praetorian Guard almost immediately after Caligula is killed.