Caligula was the nickname of the Roman emperor Gaius Julius Caesar Augustus Germanicus who ruled the empire from 37 to 41 AD. This nickname, which translates as "little boots" was used to differentiate Caligula from his father Germanicus Julius Caesar and other Roman royals with similar names.
Caligula is most remembered for the final two years of his reign where he lived a life of sexual excess while suffering from insanity.
Kinkly explains Caligula
During the early years of his reign, historical records show that Caligula was a progressive leader who instituted many positive changes for the empire. He launched new building projects for the city of Rome and expanded the empire by conquering overseas provinces. However, it’s the years following a serious bout of encephalitis which sent Caligula mad that he is most remembered for.
This period of Caligula’s reign was characterized by sexual excess and depravity. During this time he had incestuous encounters with at least two of his three sisters, hosted orgies, and raped male and female courtiers and other individuals. Records show that he also acted as a pimp for his sisters. He showed little regard for the people of Rome and matters of the state and indulged in lavish spending sprees which put the empire in a significant financial hole. He attempted to build the empire’s coffers back up by opening a lavishly decorated brothel in the palace helmed by the wives of local senators. His reign came to an end when he was assassinated by his own guards.
A 1979 film adaptation of Caligula’s life is largely regarded as the most graphic, non-pornographic film ever made for its full-frontal male and female nudity and depictions of oral sex, vaginal sex, sadomasochism, orgies, and incest.