Alexander the Great was a student of Aristotle who became King of Macedonia at age 20 after his father Philip II was murdered. Over the next decade, Alexander conquered one of the largest empires in the ancient world by defeating Darius of Persia and expanding his empire across Asia Minor and into Egypt, Mesopotamia, and India. However, his troops rebelled and refused to advance further into India. Alexander established many new cities and spread Greek culture throughout his empire before dying mysteriously at age 33, after which his empire was divided among three of his generals.