Caligula , A.D. 12–A.D. 41, Roman emperor (A.D. 37–A.D. 41); son of Germanicus Caesar and Agrippina the Elder. His real name was Caius Caesar Germanicus. As a small child, he wore military boots, whence his nickname [caligula=little boot]. On the death of Tiberius the army helped make Caligula emperor. Shortly afterward he became severely ill; it is widely believed that he was thereafter insane. He earned a reputation for ruthless and cruel autocracy, and torture and execution became the order of the day. He was responsible for serious disturbances among the Jews, and he nearly caused a rebellion in Palestine by attempting to erect a statue of himself in their temple. He was assassinated by a tribune of the Praetorian Guard and succeeded by Claudius I.