Born in Pella in 382 BC, he was King Amyntas III of Macedon and Queen Eurydice's youngest son, but the deaths of his elder brothers Kings Alexander II of Macedon and Perdiccas III of Macedon allowed him to take the throne in 359 BC. He was originally appointed as Regent till his infant nephew King Amyntas IV of Macedon, Perdiccas' son, reached adulthood, but soon he managed to make himself king. His military skills and expansionist vision of Macedonian greatness brought him early success, and it was not until his armies were opposed by Athens at Thermopylae in 352 BC that he faced any serious resistance. In 346 BC, he intervened effectively in the war between Thebes and Phocis, but his war with Athens continued intermittently. Having defeated an alliance of Thebans and Athenians at the battle of Chaeronea in 338 BC, he created and led the League of Corinth.