Macedonia disintegrated because Philip’s brothers King Alexander II, assassinated in 367 b.c.e., and King Perdiccas III, who died in battle in 359 b.c.e., were unable to stop the overwhelming foreign attacks. The Thracians already possessed eastern Macedonia. Thebes, capital of Illyria, which bordered western Macedonia, occupied northwest Macedonia.
From 368 to 365 b.c.e. Philip was a political hostage in Thebes and lived in the house of Pammenes. The learned Epaminondas taught him Greek lifestyle, customs, military tactics, and diplomacy. Upon his return to Macedonia Philip helped reform the Macedonian army.
Despite the reforms Macedonia suffered 4,000 casualties, Perdiccas among them, in a battle against Illyrian king Bardylas in 359 b.c.e. The energetic, diplomatic, yet ruthless Philip ascended the throne at age 21, overthrowing his nephew Amyntas IV, the infant son of Perdiccas.
Philip sought to advance in his political and military pursuits by reorganizing the Macedonian army, which was patterned after the Greek-style phalanx. His uniquely Macedonian phalanx gave each hoplite a longer, 18-foot spear called a sarissa. The eight to 16 rows of the phalanx moved toward the enemy, easily killing them from a distance of 20 feet.
Another of Philip’s innovations was the creation of a professional army with financial support that enticed enlistment. The newly organized Macedonian army instilled pride and strong loyalty toward Philip. Philip freed the northwest from the Illyrians by decisively defeating them in 358 b.c.e.
Philip used numerous marriages to cement political alliances. Among his wives were Illyrian princess Audata, Phila, and Princess Olympias of Epirus, daughter of Neoptolemus, who gave him a son, Alexander, in 356 b.c.e.
Philip decided he wanted the strategically important city-state of Amphipolis returned to Macedonia and captured it in 357 b.c.e., giving him access to the forests and ownership of the gold mine of Mount Pangeus.
Philip captured the town of Crenides, which had been occupied by Thracians in 356 b.c.e., renaming it Phillipi and eliminating Thrace as a threat. The Greek cities of Potidaea and Paydna were captured in 356 b.c.e. He exiled non-Macedonians and sold them into slavery.
An arrow cost Philip his right eye at the Battle for Methone in 354 b.c.e. where he defeated his enemy Argaeus. Philip was in control of Thessaly by 352 b.c.e. Demosthenes delivered three speeches from 351 to 349 b.c.e. denouncing Philip. He also conquered Olynthus in 348 b.c.e. and sold the Greeks into slavery. Within a few years he defeated 34 Greek city-states, including Stageira, the birthplace of Aristotle.
In 346 b.c.e. the Thebans asked his support in their "Sacred War" with the Phocians. Philip destroyed the Phocian city at the Battle of Crocus Field. He made peace with Athens in 346 b.c.e. but six years later waged war by besieging Byzantium and Perinthus.
Greek resistance emerged against the "barbarian" Philip who had ruthlessly suppressed Illyrian, Thracian, Greek, and Epirote rebellions. By 339 b.c.e. he defeated the Scythians near the Danube River and took 20,000 Scythian women and children as slaves. During this battle Philip was injured in his upper leg causing him to become permanently lame.
In order to conquer Greece Philip amassed a large Macedonian army and sent his 18-year-old son Alexander to command the left wing of the phalanx as a general. The Battle of Chaeronea was fought on August 2, 338 b.c.e. The Greeks had 35,000 infantry and 2,000 cavalry on the field, opposed by 30,000 Macedonian infantry, leaving Philip outnumbered.
However, with outstanding military tactics Philip defeated the Greeks. He had Macedonian garrisons built at Chalcis, Thebes, and Corinth. In 337 b.c.e. Philip organized the Greek city-states into the League of Corinth, which he headed, becoming de facto king of Greece.
Philip married a noblewoman, Cleopatra, niece of his general Attalus. This act caused a fissure with Alexander, who fled with his mother to Epirus, her home country. Philip and Cleopatra had a son named Caranus. In 336 b.c.e. Philip began his invasion of Persia but stayed behind to attend the wedding celebration of his daughter Cleopatra to Alexander of Epirus, the brother of Olympias.
The Macedonian nobleman Pausanius assassinated Philip during the wedding and was immediately executed. Cleopatra and Caranus were later murdered. It was the legacy of Alexander III to destroy Persia and create the largest kingdom of antiquity. Alexander would not have been as spectacularly successful had Philip not made Macedonia a superpower.