Julius Caesar started his career as a prosecutor in Rome. He then led military campaigns in Gaul for 9 years, where he built up his army. He later forcibly took control of Rome from his political rivals. One of his rivals fled to Egypt and was killed. Caesar proclaimed himself dictator of Rome in 44 BC but was assassinated one month later. His grandnephew Octavian, who later became Emperor Augustus, was one of the leaders who took power after his death.