By the beginning of the sixth century B. C. the athletic spirit displayed in the Homeric poems had given rise to the four national festivals—at Olympia, Delphi, Nemea, and on the Isthmus. On these four, many lesser games were modeled.[77] The origin of all these, as we have already remarked, is lost in a mass of legend. The myths of the origin of Olympia are particularly conflicting. We are practically certain, however, that Olympia as a sanctuary preceded the advent of the Achæans into the Peloponnesus, and that the foundation of the games preceded the coming of the Dorians, but was probably later than that of the Achæans. The importance of the games dates from the time after the Dorian invasion of the Peloponnesus, when the warring peoples finally became pacified.[78] For centuries Olympia was overshadowed by Delphi and the Ionian festival on Delos. The importance of the latter festival in the eighth and seventh centuries B. C. is shown by the Homeric Hymn to the Delian Apollo. Only by the beginning of the seventh century had Olympia begun to gain its prestige. The pre-Dorian Pisatai, in whose territory the sanctuary was situated, probably controlled it early. The Dorian allies, the Eleans, whom legend had King Oxylos lead into the Peloponnesus from Aitolia,[79] tried to wrest this control from the Pisatai, who, however, aided by religious reverence for the sanctuary, were able to maintain their rights. On account of the conflict the games languished, until finally a truce was made by the two factions and the games were re-established under their common management. This work was ascribed to Iphitos and Kleosthenes, kings respectively of Elis and Pisa, and to Lykourgos of Sparta.[80] The dual control was not successful, as the jealous Pisatai constantly tried to regain their old honor; but the Eleans, supported by the Spartans, prevailed and finally, after the Persian wars, destroyed Pisa and the other revolting cities of Triphylia and henceforth remained in sole control. The restoration of the games under Iphitos and his colleagues took place in 776 B. C., from which date the festival was celebrated every fourth year, until it was finally abolished by the Roman emperor Theodosius at the end of the fourth century A. D. In 776 Koroibos of Elis won the foot-race and this was the first dated Olympiad in the Olympian register,[81] and from it, as Pausanias says,[82] the unbroken tradition of the Olympiads began. This history of Olympia is very different from the orthodox mythical story told by Pausanias and Strabo and based on the “ancient writings of the Eleans.”[83] According to it the games were originally instituted by the Eleans under Oxylos and refounded by Iphitos, his descendant, together with Lykourgos, still under the management of the Eleans. In Ol. 8 the Pisatans invoked the aid of the Argive king Pheidon and dispossessed the Eleans, but they lost the control of Olympia in the next Olympiad. In Ol. 28 Elis,