Territorial evolution of the Ottoman Empire
Suleiman I ( "Süleymān", ; almost always "Kanuni Sultan Süleyman") (6 November 1494  – 5/6/7 September 1566), was the tenth and longest-reigning Sultan of the Ottoman Empire, from 1520 to his death in 1566. Suleiman became a prominent monarch of 16th century Europe. Suleiman personally led Ottoman armies to conquer the Christian strongholds of Belgrade, Rhodes, and most of Hungary. In 1541 he annexed central Hungary while Transylvania became an Ottoman vassal. However rest of the Kingdom of Hungary including western and northern (Upper) Hungary and Croatia still were Habsburgs possessions. Suleiman also conquered Iraq in his conflict with the Safavid dynasty. Under his rule, the Ottoman fleet dominated the seas from the Mediterranean to the Red Sea and the Persian Gulf.
Ottoman dynasty
The Ottoman dynasty operated under several basic premises: that the Sultan governed the empire’s entire territory, that every male member of the dynastic family was hypothetically eligible to become Sultan, and that only one person at a time could be the Sultan. Such rules were fairly standard for monarchic empires of the time. The certain processes through which men rose to the Sultanate, however, were very specific to the Ottoman Empire. To go into greater detail about these processes, the history of succession between Sultans can be divided into two eras: the period between the reign of Orhan (1323-1362), the first person to inherit the Ottoman sultanate, and the reign of Ahmed I (1603-1617); and the period following Ahmed I’s reign.