We think, then, that the prestige of the Delphian Apollo, though originating in the Dorian migration, was due to a combination of two forces: (1) the widespread cult of Apollo in Greece and in Asia Minor: and (2) the skill by which the Delphians (who controlled the oracular decrees) impressed the Greeks and foreign peoples with the unrivalled divinity of their local shrine in matters of prophecy and healing-magic; and organised under their banner the local priesthoods of Greece by annual processions and pilgrimages, by the construction of sacred roads, and the establishment of religious Amphictyonies.[160] While other ‘sacerdotal’ nobles in Greece worshipped a number of deities, Olympian and Chthonian, the Delphians seem to have concentrated on Apollo. They were definitely theocratic—being a select caste of nobles, whose High Priests were elected by lot.[161] They formed a criminal court which exacted the death penalty for sacrilege. It follows that when homicide became a religious offence, these judges would not only have decided all cases within their territory,[162] distinguished between different degrees of guilt, and pronounced upon the possibility of purgation, but they would also have used the prestige of the oracle to make their decisions imitated elsewhere. Thus, the Attic Eupatridae, who worshipped Apollo Patroos, and their judges, the Ephetae, who swore by him before their trials,[163] would naturally have adopted the decisions of the central Apolline oracle. Moreover, the annual processions of representatives (θεωροί) of Greek states to Delphi, the Pythian Games, a festival in which all Greeks participated, and the formation of religious international leagues or Amphictyonies made obedience to Apolline oracles almost a matter of obligation. The great Thessalian Amphictyony of Demeter at Anthela, a very ancient association, including Thessalians, Locrians, Phocians, Boeotians, Athenians, Dorian and minor states, came in the sixth century[164] to meet also at Delphi, and the temple was placed under the control of international Hieromnemones who met twice a year and promulgated laws to be obeyed by all its members, called Amphictyonic laws. It is significant that, in historical Athens, murder exiles were prohibited from Amphictyonic festivals.[165] This law was clearly of Amphictyonic origin.[166] We have quoted Thucydides’[167] account of the command which was issued by the oracle of Apollo to Alcmaeon, the matricide, directing him to travel to the Echinades Islands. This legend bears, on the face of it, an antique stamp, and the function which is here ascribed to the Delphic oracle is a first-rate piece of evidence for the connexion of Apollo with the historical doctrine of ‘pollution.’