or Osman, the founder of the Ottoman Empire, was born in Bithynia in 1259. He is said to have been the son of Orthogruh, the chief of a pastoral and predatory horde of Turkomans, who had permanently pitched their tents in the territory of the Sultan of Iconium. At any rate, it is certain, that on the death of Masud II., the last of the Seljukian dynasty, he was at the head of the above- mentioned tribe, and was ready to begin the project of founding a kingdom. Part of Bithynia, a fragment of the dismembered empire of the sultans of Iconium, was immediately seized; a government was established; coins were struck in the city of Cara-Hissar; and on the 27th July 1299 he led his invading forces down through the unguarded passes of Mount Olympus into the territory of Nicea. The conquest advanced slowly but successfully for the next twenty-seven years. The hardy robber-chief, after repeated incursions, began to gain ground upon the Greeks; captives and volunteers soon swelled the number of his troops; he was then enabled, by means of garrisons, to secure every post as soon as it was taken; the different districts of Bithynia came successively under his power; and the foundation of the Ottoman Empire was completed by the capture of Prusa in 1326. Othman had just time to hear the news before he died, leaving his sceptre to his son Orchan. (See Turkey.)