Gaius Caesar Augustus Germanicus (31 August AD 12 – 24 January AD 41), also called Gaius and Caligula (), was Roman emperor from AD 37 until his assassination in AD 41. He was the son of the Roman general Germanicus and Augustus' granddaughter Agrippina the Elder, members of the first ruling family of the Roman Empire. He was born two years before Tiberius became emperor. Gaius accompanied his father, mother and siblings on campaign in Germania, at little more than four or five years old. He had been named after Gaius Julius Caesar, but his father's soldiers affectionately nicknamed him "Caligula" ('little boot').
Germanicus died in Antioch in AD 19, and Agrippina returned with her six children to Rome, where she became entangled in a bitter feud with Emperor Tiberius, who was Germanicus' biological uncle and adoptive father. The conflict eventually led to the destruction of her family, with Caligula as the sole male survivor. In 26, Tiberius withdrew from public life to the island of Capri, and in 31, Caligula joined him there.