Delphi
In 356 BC the Phocians under Philomelos captured and sacked Delphi, leading to the Third Sacred War (356–346 BC), which ended with the defeat of the former and the rise of Macedon under the reign of Philip II. This led to the Fourth Sacred War (339 BC), which culminated in the Battle of Chaeronea (338 BC) and the establishment of Macedonian rule over Greece.
In Delphi, Macedonian rule was superseded by the Aetolians in 279 BC, when a Gallic invasion was repelled, and by the Romans in 191 BC. The site was sacked by Lucius Cornelius Sulla in 86 BC, during the Mithridatic Wars, and by Nero in 66 AD. Although subsequent Roman emperors of the Flavian dynasty contributed towards to the restoration of the site, it gradually lost importance. In the course of the 3rd century mystery cults became more popular than the traditional Greek pantheon. Christianity, which started as yet one more mystery cult, soon gained ground, and this eventually resulted in the persecution of pagans in the late Roman Empire. The anti-pagan legislation of the Flavian dynasty deprived ancient sanctuaries of their assets. The emperor Julian attempted to reverse this religious climate, yet his "pagan revival" was particularly short-lived. When the doctor Oreibasius visited the oracle of Delphi, in order to question the fate of paganism,he received a pessimistic answer:
Third Sacred War
Now that he was in control of Thermopylae, Philip could be certain of dictating the terms of the end of the Sacred War, since he could now use force against any state that did not accept his arbitration. He began by making a truce with Phalaikos on 19 July; Phalaikos surrendered Phocis to him, in return for being allowed to leave with his mercenaries and go wherever he wished. Cawkwell suggests that Phalaikos probably collaborated with Philip in 346 BC, allowing Philip to take Thermopylae in return for lenience for him and his men. Otherwise, it is difficult to see how Philip could have advertised his campaign so far in advance (and been so confident of success), and yet not been stopped at Thermopylae. Philip restored to Boeotia the cities that Phocis had captured during the war (Orchomenos, Coroneia and Corsiae), and then declared that the fate of Phocis would not be decided by him, but by the Amphictyonic Council. This caused great panic in Athens, since the Phocians could never hope for mercy from the Amphictyons, and since Athens had also (having allied with Phocis) shared in the same sacrilege. However, it is clear that Philip was dictating the terms behind the scenes; allowing the Amphictyons the formal responsibility allowed him to dissociate himself from the terms in the future.