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.
Battle of Crocus Field
The ancient sources for the Third Sacred War are scant, and generally lacking in firm chronological information. The main source for the period is Diodorus Siculus's "Bibliotheca historica", written in the 1st century BC, which is therefore very much a secondary source. Diodorus is often derided by modern historians for his style and inaccuracies, but he preserves many details of the ancient period found nowhere else. Diodorus worked primarily by epitomizing the works of other historians, omitting many details where they did not suit his purpose, which was to illustrate moral lessons from history; his account of the Third Sacred War therefore contains many gaps.