In 353 BC, a third Sacred War broke out when Thebes had placed a fine upon Phocis, and Phocis, to pay for the war, heavily taxed the people of nearby Delphi and seized the Treasury of Delphi. The Amphictyonic League led by Philip declared war against Phocis. Philip sought to unite all Greece with Macedon in the Amphictyonic League to attack Persia.