2. The political power of the Dorians over the whole of Peloponnesus necessarily ensured the preponderance of their religious institutions; nevertheless we find that the Achæans and Arcadians possessed few temples of Apollo, and those not the principal ones in their cities.(1080) The worship of Apollo was however, through Spartan influence, held in great respect at Tegea (the customs of which town had indeed become almost entirely Doric), where there was also a tribe called Apolloneatis.(1081) The country moreover being intersected in every direction by roads to Olympia and Delphi (to which place Peloponnesus despatched her hecatombs in the beginning of the spring),(1082) must have been by this very circumstance induced to establish temples in honour of Apollo, an instance of which appears in that at Onceum. The principal deity of the Doric name soon obtained a conspicuous place in the national festival, held equally sacred by all Peloponnesians; I mean that of Olympia. The establishment of this festival is probably of early date; perhaps it took place during the time when the dominion of the Pelopidæ spread from Pisa and Olympia over most parts of the peninsula. Hence the Elean Ætolians, when they seized upon the presidency of these games, were, by the command of the oracle, at the same time obliged to take one of the Pelopidæ from the Achæan town of Helice for their prince.(1083) Moreover, the ancient rivalry between the Olympian and Isthmian worship, which occasioned the prohibition against any Elean contending at the Isthmus,(1084) can hardly have arisen at any other time than when (previously to the Doric usurpation) the Olympian Zeus was the chief god of the Achæans,(1085) the Isthmian Poseidon of the Ionians.