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
Some early Ottoman Sultans even had to accept the vassal status in the eyes of a foreign overlord. For example, Tamerlane appointed in 1402 the Ottoman Sultan Süleyman Çelebi (deposed in 1411), who was styled "as-Sultan ul-Azam, Sayyid us-Saladin ul-Arab wal Ajam, Malik ur-Rikaab ul-Umam, Ghiyas ud-Daula wa ud-Dunya, Sultan ul-Islam wal-Muslimin, as-Sultan ibni us-Sultan, Hasib-i-Nasib-I-Zaman, Amir ul-Rumelia" (Grand Sultan, Righteous Lord of Arabs, Helper of the State and the People, Sultan of Islam and the Muslims, Sultan son of Sultans, Prince of Rumelia). Again his brother, Mehmed I, who ended the Ottoman Interregnum, also held his post with a fief from Tamerlane; he took the title "Sovereign of the House of Osman, Khan of Khans, Grand Sultan of Anatolia and Rumelia, and of the Cities of Adrianople and Philipopolis". However, the vassalage of the Ottoman Sultanate ended with the death of Tamerlane during the reign of the next Ottoman ruler, Sultan Murad II, who took the style "Sultan ul-Mujahidin, Sovereign of the House of Osman, Khan of Khans, Grand Sultan of Anatolia and Rumelia, and of the Cities of Adrianople and Philipopolis".