Alexander the Great was 

A king of the ancient Greek kingdom of Macedon. He succeeded his father Philip II to the throne in 336 BC at the age of 20, and spent most of his ruling years conducting a lengthy military campaign throughout Western Asia and Northeastern Africa. By the age of thirty, he had created one of the largest empires in history, stretching from Greece to northwestern India. He was undefeated in battle and is widely considered to be one of historys greatest and most successful military commanders. During his youth, Alexander was tutored by Aristotle until the age of 16. In 335 BC he campaigned in the Balkans, reasserting control over Thrace and Illyria before sacking the Greek city of Thebes. Alexander was then awarded the generalship of Greece. He used his authority to launch his fathers Pan-Hellenic project, assuming leadership over all the Greeks in their conquest of Persia. He eventually turned back at the Beas River due to the demand of his homesick troops, dying in 323 BC in Babylon, the city he planned to establish as his capital. He founded more than twenty cities that bore his name, most notably Alexandria in Egypt. Alexanders settlement of Greek colonists and the resulting spread of Greek culture resulted in Hellenistic civilization, which developed through the Roman Empire into modern Western culture. His military achievements and enduring, unprecedented success in battle made him the measure against which many later military leaders would compare themselves. Military academies throughout the world still teach his tactics.

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