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 Caliphate
The Ottoman Caliphate (1517–1924), under the Ottoman dynasty of the Ottoman Empire, was the last Sunni Islamic caliphate of the late medieval and the early modern era. During the period of Ottoman growth, Ottoman rulers claimed caliphal authority since Murad I's conquest of Edirne in 1362. Later Selim I, through conquering and unification of Muslim lands, became the defender of the Holy Cities of Mecca and Medina which further strengthened the Ottoman claim to caliphate in the Muslim world.