Besides the conquests above mentioned, Hippokratês of Gela was on the point of making the still more important acquisition of Syracuse, and was only prevented from doing so, after defeating the Syracusans at the river Helôrus, and capturing many prisoners, by the mediation of the Corinthians and Korkyræans, who prevailed on him to be satisfied with the cession of Kamarina and its territory as a ransom. Having repeopled this territory, which became thus annexed to Gela, he was prosecuting his conquests farther among the Sikels, when he died or was killed at Hybla. His death caused a mutiny among the Geloans, who refused to acknowledge his sons, and strove to regain their freedom; but Gelo, the general of horse in the army, espousing the cause of the sons with energy, put down by force the resistance of the people. As soon as this was done, he threw off the mask, deposed the sons of Hippokratês, and seized the sceptre himself.[430] [430] Herodot. vii, 155; Thucyd. vi, 5. The ninth Nemean Ode of Pindar (v, 40), addressed to Chromius the friend of Hiero of Syracuse, commemorates, among other exploits, his conduct at the battle of the Helôrus. Thus master of Gela, and succeeding probably to the ascendency enjoyed by his predecessor over the Ionic cities, Gelo became the most powerful man in the island; but an incident which occurred a few years afterwards (B. C. 485), while it aggrandized him still farther, transferred the seat of his power from Gela to Syracuse. The Syracusan Gamori, or oligarchical order of proprietary families, probably humbled by their ruinous defeat at the Helôrus, were dispossessed of the government by a combination between their serf-cultivators, called the Kyllyrii, and the smaller freemen, called the Demos; they were forced to retire to Kasmenæ, where they invoked the aid of Gelo to restore them. That ambitious prince undertook the task, and accomplished it with facility; for the Syracusan people, probably unable to resist their political opponents when backed by such powerful foreign aid, surrendered to him without striking a blow.[431] But instead of restoring the place to the previous oligarchy, Gelo appropriated it to himself, and left Gela to be governed by his brother Hiero. He greatly enlarged the city of Syracuse, and strengthened its fortifications: probably it was he who first carried it beyond the islet of Ortygia, so as to include a larger space of the adjacent mainland (or rather island of Sicily) which bore the name of Achradina. To people this enlarged space, he brought all the residents in Kamarina, which town he dismantled,—and more than half of those in Gela; which was thus reduced in importance, while Syracuse became the first city in Sicily, and even received fresh addition of inhabitants from the neighboring towns of Megara and Eubœa. Both these towns, like Syracuse, were governed by oligarchies, with serf cultivators dependent upon them, and a Dêmos, or body of smaller freemen,