Alexander III of Macedon, commonly known as Alexander the Great, was a king of the ancient Greek kingdom of Macedon. A member of the Argead dynasty, he was born in Pella—a city in Ancient Greece—in 356 BC. He succeeded his father King Philip II to the throne 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 history's greatest and most successful military commanders.
During his youth, Alexander was tutored by Aristotle until the age of 16. His father Philip was assassinated in 336 BC at the wedding of Cleopatra of Macedon, Alexander's sister, and Alexander assumed the throne of the Kingdom of Macedon. After sacking the city of Thebes, Alexander was awarded the generalship of Greece. He used his authority to launch his father's pan-Hellenic project, which involved him assuming the leadership position to all the Greeks in their conquest of Persia.