Delphi was an ancient Greek city that housed the most important oracle of the ancient Greek world. The city is mentioned from Homeric times under the name Pytho. At the beginning of the historical era, it was one of the cities of ancient Phocis, but over time, its role grew and it evolved into a pan-Hellenic center and sacred city of the ancient Greeks. It also served as the center of the Delphic Amphictyony.
Delphi maintained its significance until the late 4th century AD, when the operation of the oracle was definitively ended by a decree of Emperor Theodosius I. In the following centuries, the city declined and was eventually abandoned during the Slavic invasions.