On the expulsion of Hippias, Clis'thenes, to whom Athens was mainly indebted for its liberation from the Pisistratids, aspired to the political leadership of the state. But he was opposed by Isag'oras, who was supported by the nobility. In order to make his cause popular, Clisthenes planned, and succeeded in executing, a change in the Constitution of Solon, which gave to the people a greater share in the government. He divided the people into ten tribes, instead of the old Ionic four tribes, and these in turn were subdivided into districts or townships called de'mes. He increased the powers and duties of the Senate, giving to it five hundred members, with fifty from each tribe; and he placed the administration of the military service in the hands of ten generals, one being taken from each tribe. The reforms of Clisthenes gave birth to the Athenian democracy. As THIRLWALL observes, "They had the effect of transforming the commonalty into a new body, furnished with new organs, and breathing a new spirit, which was no longer subject to the slightest control from any influence, save that of wealth and personal qualities, in the old nobility. The whole frame of the state was reorganized to correspond with the new division of the country." On the application of Isagoras and his party, Sparta, jealous of the growing strength of Athens, made three unsuccessful attempts to overthrow the Athenian democracy, and reinstate Hippias in supreme command. She finally abandoned the project, as she could find no allies to assist in the enterprise. "Athens had now entered upon her glorious career. The institutions of Clisthenes had given her citizens a personal interest in the welfare and the grandeur of their country, and a spirit of the warmest patriotism rapidly sprung up among them. The Persian wars, which followed almost immediately, exhibit a striking proof of the heroic sacrifices which they were prepared to make for the liberty and the independence of their state." CHAPTER VII. A BRIEF HISTORY OF THE GREEK COLONIES.