Third Sacred War
The Third Sacred War (356–346 BC) was fought between the forces of the Delphic Amphictyonic League, principally represented by Thebes, and latterly by Philip II of Macedon, and the Phocians. The war was caused by a large fine imposed in 357 BC on the Phocians by the Amphictyonic League (dominated at that moment by Thebes), for the offense of cultivating sacred land; refusing to pay, the Phocians instead seized the Temple of Apollo in Delphi, and used the accumulated treasures to fund large mercenary armies. Thus, although the Phocians suffered several major defeats, they were able to continue the war for many years, until eventually all parties were nearing exhaustion. Philip II used the distraction of the other states to increase his power in northern Greece, in the process becoming ruler of Thessaly. In the end, Philip's growing power, and the exhaustion of the other states, allowed him to impose a peaceful settlement of the war, marking a major step in the rise of Macedon to pre-eminence in Ancient Greece.
Expansion of Macedonia under Philip II
The ancient sources for the sacred war are scant, and generally lacking in firm chronological information. Modern historians' dates for the war have therefore been hotly debated, with no clear consensus. It is generally accepted that the war lasted 10 years, and ended in summer 346 BC (one of the only firm dates), which yields a date of 356 BC for the beginning of the war, with Philomelos's seizure of Delphi. After Philomelos's defeat at Neon, the Thebans thought it safe to send the general Pammenes to Asia with 5000 hoplites; as has been discussed, Pammenes probably met with Philip at Maroneia in 355 BC, presumably on his outward journey. Buckler, the only historian to produce a systematic study of the sacred war, therefore places Neon in 355 BC, and suggests after the meeting with Pammenes, Philip went to begin the siege of Methone. Other historians have placed Neon in 354 BC, because Diodorus says that the battle took place while Philip besieged Methone which Diodorus (at one point) places in 354 BC. However, Diodorus's chronology for the sacred war is very confused—he dates the start and end of the war a year too late, variously says the war lasted 9, 10 or 11 years, and included the siege of Methone twice under different dates—and his dates cannot therefore be relied upon.