In history, many great generals were also political leaders. Julius Caesar was a general who became the dictator of Rome in 44 BC. Genghis Khan was the son of a Mongol chieftain who became a general and then the leader of the Mongol Empire. As a general, Alexander the Great never lost a battle. He was a king who was also a general. In the British Army of the 17th and 18th centuries, the officers were often aristocrats and most obtained their rank by purchase.