Caius Caesar was born in 12 A.D., the son of Germanicus and Agrippina Sr. He was nicknamed Caligula , meaning "little boots," by the legions because as a child his mother dressed him in military uniforms (including little boots). Initially he was very popular, succeeding Tiberius in 37 A.D. and for a few brief months ruling very well. However, an unknown disease drove him mad and his reign soon degenerated into debauchery and murder. He was murdered by the Praetorian Guard in 41 A.D.