During his youth, Alexander was tutored by Aristotle until age 16. After Philip's assassination in 336 BC, he succeeded his father to the throne and inherited a strong kingdom and an experienced army. Alexander was awarded the generalship of Greece and used this authority to launch his father's pan-Hellenic project to lead the Greeks in the conquest of Persia.[4][5] In 334 BC, he invaded the Achaemenid Empire (Persian Empire) and began a series of campaigns that lasted 10 years. Following the conquest of Anatolia, Alexander broke the power of Persia in a series of decisive battles, most notably the battles of Issus and Gaugamela. He subsequently overthrew Persian King Darius III and conquered the Achaemenid Empire in its entirety.[b] At that point, his empire stretched from the Adriatic Sea to the Beas River.
Alexander endeavoured to reach the "ends of the world and the Great Outer Sea" and invaded India in 326 BC, winning an important victory over the Pauravas at the Battle of the Hydaspes. He eventually turned back at the demand of his homesick troops, dying in Babylon in 323 BC, the city that he planned to establish as his capital, without executing a series of planned campaigns that would have begun with an invasion of Arabia. In the years following his death, a series of civil wars tore his empire apart, resulting in the establishment of several states ruled by the Diadochi, Alexander's surviving generals and heirs.
Alexander's legacy includes the cultural diffusion and syncretism which his conquests engendered, such as Greco-Buddhism. He founded some twenty cities that bore his name, most notably Alexandria in Egypt. Alexander's settlement of Greek colonists and the resulting spread of Greek culture in the east resulted in a new Hellenistic civilization, aspects of which were still evident in the traditions of the Byzantine Empire in the mid-15th century AD and the presence of Greek speakers in central and far eastern Anatolia until the Greek genocide by the Turks in the 1920s. Alexander became legendary as a classical hero in the mould of Achilles, and he features prominently in the history and mythic traditions of both Greek and non-Greek cultures. He was undefeated in battle and became the measure against which military leaders compared themselves. Military academies throughout the world still teach his tactics.[6][c] He is often ranked among the most influential people in history.[7]