The Ottoman Empire was founded in 1299, by Osman I, an Oghuz Turk from Anatolia. He conquered the Byzantine city of Bilecik, and made it his capital. During the rest of his life, until his death in 1324, he continued to conquer Byzantine cities through Anatolia. His son, Orhan, continued the expansion and the capital of the empire moved to Bursa. Orhan also married the daughter of a Byzantine prince, then supported his father-in-law in overthrowing the emperor of the Byzantine Empire, for which he received the peninsula of Gallipoli and the first Muslim stronghold within Europe.
At the height of its power the Ottomans claimed to control the North African coast, the Nile valley, parts of the coastlines of the Red Sea and the Iranian Gulf, all of Turkey and the Eastern Mediterranean deep into modern Iraq/Iran, almost the entire coast of the Black Sea, and Europe as far north as Hungary.