The site of Delphi served as a cultic center beginning some time before the 10th century B.C. Votives were used ca. 800 B.C. and within a century the oracle of the priestess Pythia came here. When the cult of Apollo Delphinios (worship of an island deity in dolphin form) was brought to the region from Crete, the city acquired its name "Delphi." After the Dorian Invasion in 1100 B.C., the sanctuary at Delphi became the center for the Amphictyonic League, a group of 12 tribes representing city-states throughout the surrounding regions. It included Thessalians, Achaeans, Ionians, Dorians, and cities such as Athens and Sparta.
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