his son in 338 BC, and they marched south through Thermopylae, taking it after stubborn resistance from its Theban garrison. They went on to occupy the city of Elatea, only a few days' march from both Athens and Thebes. The Athenians, led by Demosthenes, voted to seek alliance with Thebes against Macedonia. Both Athens and Philip sent embassies to win Thebes's favour, but Athens won the contest. Philip marched on Amphissa (ostensibly acting on the request of the Amphictyonic League), capturing the mercenaries sent there by Demosthenes and accepting the city's surrender. Philip then returned to Elatea, sending a final offer of peace to Athens and Thebes, who both rejected it. As Philip marched south, his opponents blocked him near Chaeronea, Boeotia. During the ensuing Battle of Chaeronea, Philip commanded the right wing and Alexander the left, accompanied by a group of Philip's trusted generals. According to the ancient sources, the two sides fought bitterly for some time. Philip deliberately commanded his troops to retreat, counting on the untested Athenian hoplites to follow, thus breaking their line. Alexander was the first to break the Theban lines, followed by Philip's generals. Having damaged the enemy's cohesion, Philip ordered his troops to press forward and quickly routed them. With the Athenians lost, the Thebans were surrounded. Left to fight alone, they were defeated. After the victory at Chaeronea, Philip and Alexander marched unopposed into the Peloponnese, welcomed by all cities; however, when they reached Sparta, they were refused, but did not resort to war. At Corinth, Philip established a "Hellenic Alliance" (modelled on the old anti-Persian alliance of the Greco-Persian Wars), which included most Greek city-states except Sparta. Philip was then named Hegemon (often translated as "Supreme Commander") of this league (known by modern scholars as the League of Corinth), and announced his plans to attack the Persian Empire. Exile and return When Philip returned to Pella, he fell in love with and married Cleopatra Eurydice in 338 BC, the niece of his general Attalus. The marriage made Alexander's position as heir less secure, since any son of Cleopatra Eurydice would be a fully Macedonian heir, while Alexander was only half-Macedonian. During the wedding banquet, a drunken Attalus publicly prayed to the gods that the union would produce a legitimate heir. In 337 BC, Alexander fled Macedon with his mother, dropping her off with her brother, King Alexander I of Epirus in