In Archaic Greece, an amphictyony (, a "league of neighbors"), or amphictyonic league, was an ancient religious association of tribes formed before the rise of the Greek poleis.
The six Dorian cities of coastal southwest Anatolia and the twelve Ionian cities to their north that formed the Ionian League after a Meliac war in the mid-7th century BC were already of considerable antiquity when the first written records emerge.

An amphictyony consisting of polities under the aegis of Apollo's shrine at Delos was apparently well-established in the seventh century, as the Homeric Hymn to Delian Apollo of that approximate date lists them, those cities and islands that trembled and refused to offer themselves for the birthplace of Apollo when pregnant Leto went to each in turn; the Homeric hymn presents an origin myth for the cult of Apollo on Delos. The joint Ionian festival celebrated there was the Delia. The Delian Amphictyony arose in the 4th century BC as an instrument of Athenian hegemony.

Ancient historiography
Thucydides made recollection of the Lelantine War, apparently fought in Euboea sometime between the late 8th century BC and the first half of the 7th century BC: "The war between Chalcis and Eretria was the one in which most cities belonging to the rest of Greece were divided up into alliances with one side or the other."

Historians have puzzled over the broader meanings of "alliance" in such early times. "But comparatively large-scale associations lead more readily to contacts, to friendships and enmities at a distance than do little city-like units," George Forrest notes, remarking apropos that Phrygia and Assyria were at war with each other about 720–710, raising tensions among interested Greeks.
In historic times, an amphictyony might survive as a form of religious organization enjoined to support specific temples or sacred places; traditional amphictyonies coordinated Olympic and Pythian Games. Twelve members would meet at specific times in the same sanctuary to keep religious festivals and conduct other matters as well.
An early amphictyony centered on Kalaureia, an island close to the coast of Troezen in the Peloponnese sacred to Poseidon, was noted by Strabo. Archaeology of the site suggested to Thomas Kelly that the sacred league was founded in the second quarter of the 7th century BCE, c. 680–650; before that date there were virtually no remains at the site, which could not have been used more than sporadically. The island was known at one time as Eirene (Εἰρήνη) ("Peace"), clearly in reference to the amphictyony. Strabo lists the poleis that belonged: "And there was also a kind of amphictyonic league connected with this temple, a league of seven cities which shared in the sacrifice; they were Hermione, Epidaurus, Aegina, Athens, Prasïeis, Nauplïeis, and Orchomenus Minyeius; however, the Argives paid dues for the Nauplians, and the Lacedaemonians for the Prasians."
Delphic Amphictyony
The least obscure and longest-lasting amphictyony was the Delphic Amphictyony or Great Amphictyonic League that was organized to support the greater temples of Apollo and Demeter. Its council had religious authority and the power to pronounce punishments against offenders (which could range from fines to expulsion), and to conduct sacred wars. The Amphictyonic League also set the rules of battle so as to protect sanctuaries and impose sentences on those who molested sanctuaries. All members were obliged to pledge themselves by an oath as reported by Aeschines.
Based on legend, the Great Amphictyonic League was founded somewhat after the Trojan War, for the protection and administration of the temple of Apollo in Delphi and temple of Demeter in Anthela (Ἀνθήλη), near Thermopylae. The founding myth claimed that it had been founded in the most distant past by an eponymous founder Amphictyon, brother of Hellen, the common ancestor of all Hellenes. Representatives of the twelve members (called hieromnemones) met in Thermopylae in spring and in Delphi in autumn.





