Philip II of Macedon was a king (basileus) of Macedon from 359 BC until his assassination in 336 BC. He was the father of Alexander the Great and Philip III.
Philip was the youngest son of the king Amyntas III and Eurydice I. In his youth, (c. 368–365 BC) Philip was held as a hostage in Thebes, which was the leading city of Greece during the Theban hegemony. While a captive there, Philip received a military and diplomatic education from Epaminondas, became eromenos of Pelopidas,and lived with Pammenes, who was an enthusiastic advocate of the Sacred Band of Thebes. In 364 BC, Philip returned to Macedon. The deaths of Philip's elder brothers, King Alexander II and Perdiccas III, allowed him to take the throne in 359 BC. Originally appointed regent for his infant nephew Amyntas IV, who was the son of Perdiccas III, Philip managed to take the kingdom for himself that same year.

Philip's military skills and expansionist vision of Macedonian greatness brought him early success. He first had to re-establish a situation which had been greatly worsened by the defeat against the Illyrians in which King Perdiccas himself had died. The Paionians and the Thracians had sacked and invaded the eastern regions of the country, while the Athenians had landed, at Methoni on the coast, a contingent under a Macedonian pretender called Argeus. Using diplomacy, Philip pushed back Paionians and Thracians promising tributes, and crushed the 3,000 Athenian hoplites (359). Momentarily free from his opponents, he concentrated on strengthening his internal position and, above all, his army. His most important innovation was doubtless the introduction of the phalanx infantry corps, armed with the famous sarissa, an exceedingly long spear, at the time the most important army corps in Macedonia.

Philip had married Audata, great-granddaughter of the Illyrian king of Dardania, Bardyllis. However, this did not prevent him from marching against them in 358 and crushing them in a ferocious battle in which some 7,000 Illyrians died (357). By this move, Philip established his authority inland as far as Lake Ohrid and the favour of the Epirotes.He agreed with the Athenians, who had been so far unable to conquer Amphipolis, which commanded the gold mines of Mount Pangaion, to lease it to them after its conquest, in exchange for Pydna (lost by Macedon in 363). However, after conquering Amphipolis, he kept both the cities (357). As Athens declared war against him, he allied with the Chalkidian League of Olynthus. He subsequently conquered Potidaea, this time keeping his word and ceding it to the League in 356. One year before Philip had married the Epirote princess Olympias, who was the daughter of the king of the Molossians.

In 356 BC, Philip also conquered the town of Crenides and changed its name to Philippi: he established a powerful garrison there to control its mines, which granted him much of the gold later used for his campaigns. In the meantime, his general Parmenion defeated the Illyrians again. Also in 356 Alexander was born, and Philip's race horse won in the Olympic Games. In 355–354 he besieged Methone, the last city on the Thermaic Gulf controlled by Athens. During the siege, Philip lost an eye. Despite the arrival of two Athenians fleets, the city fell in 354. Philip also attacked Abdera and Maronea, on the Thracian seaboard (354–353).

Involved in the Third Sacred War which had broken out in Greece, in the summer of 353 he invaded Thessaly, defeating 7,000 Phocians under the brother of Onomarchus. The latter however defeated Philip in the two succeeding battles. Philip returned to Thessaly the next summer, this time with an army of 20,000 infantry and 3,000 cavalry including all Thessalian troops. In the Battle of Crocus Field 6,000 Phocians fell, while 3,000 were taken as prisoners and later drowned. This battle granted Philip an immense prestige, as well as the free acquisition of Pherae. Philip was also tagus of Thessaly, and he claimed as his own Magnesia, with the important harbour of Pagasae. Philip did not attempt to advance into Central Greece because the Athenians, unable to arrive in time to defend Pagasae, had occupied Thermopylae.

Hostilities with Athens did not yet take place, but Athens was threatened by the Macedonian party which Philip's gold created in Euboea. From 352 to 346 BC, Philip did not again come south. He was active in completing the subjugation of the Balkan hill-country to the west and north, and in reducing the Greek cities of the coast as far as the Hebrus. To the chief of these coastal cities, Olynthus, Philip continued to profess friendship until its neighboring cities were in his hands.

In 349 BC, Philip started the siege of Olynthus, which, apart from its strategic position, housed his relatives Arrhidaeus and Menelaus, pretenders to the Macedonian throne. Olynthus had at first allied itself with Philip, but later shifted its allegiance to Athens. The latter, however, did nothing to help the city, its expeditions held back by a revolt in Euboea (probably paid by Philip's gold). The Macedonian king finally took Olynthus in 348 BC and razed the city to the ground. The same fate was inflicted on other cities of the Chalcidian peninsula. Macedon and the regions adjoining it having now been securely consolidated, Philip celebrated his Olympic Games at Dium. In 347 BC, Philip advanced to the conquest of the eastern districts about Hebrus, and compelled the submission of the Thracian prince Cersobleptes. In 346 BC, he intervened effectively in the war between Thebes and the Phocians, but his wars with Athens continued intermittently. However, Athens had made overtures for peace, and when Philip again moved south, peace was sworn in Thessaly. With key Greek city-states in submission, Philip turned to Sparta; he sent them a message, "You are advised to submit without further delay, for if I bring my army into your land, I will destroy your farms, slay your people, and raze your city." Their laconic reply: "If". Philip and Alexander would both leave them alone. Later, the Macedonian arms were carried across Epirus to the Adriatic Sea.

In 345 B.C., Philip conducted a hard-fought campaign against the Ardiaioi (Ardiaei), under their king Pluratus, during which he was seriously wounded by an Ardian soldier in the lower right leg.In 342 BC, Philip led a great military expedition north against the Scythians, conquering the Thracian fortified settlement Eumolpia to give it his name, Philippopolis (modern Plovdiv).

In 340 BC, Philip started the siege of Perinthus. Philip began another siege in 339 of the city of Byzantium. After unsuccessful sieges of both cities, Philip's influence all over Greece was compromised. However, he successfully reasserted his authority in the Aegean by defeating an alliance of Thebans and Athenians at the Battle of Chaeronea in 338 BC, while in the same year, Philip destroyed Amfissa because the residents had illegally cultivated part of the Crisaian plain which belonged to Delphi. Philip created and led the League of Corinth in 337 BC. Members of the League agreed never to wage war against each other, unless it was to suppress revolution. Philip was elected as leader (hegemon) of the army of invasion against the Persian Empire. In 336 BC, when the invasion of Persia was in its very early stage, Philip was assassinated, and was succeeded on the throne of Macedon by his son Alexander III.