Classical Age of the Ottoman Empire
Expansion continued during the first half of the reign of Suleiman I (r. 1520-1566), who conquered first Belgrade (1521) and Rhodes, before invading Hungary in 1526, defeating and killing King Louis II in the Battle of Mohács and briefly occupying Buda. Lacking a king, Hungary descended into civil war over the succession, and the Ottomans gave support to John Zápolya as a vassal prince. When their rivals the Habsburgs began to achieve the upper hand, Suleiman directly intervened by again conquering Buda and annexing it to the empire in 1541. Elsewhere, Suleiman led major campaigns against Safavid Iran, conquering Baghdad in 1534 and annexing Iraq. Ottoman rule was further extended with the incorporation of much of North Africa, the conquest of coastal Yemen in 1538, and the subsequent annexation of the interior.
Selim I
On the 22nd of September 1520, Sultan Selim I's eight year reign came to an end. Selim passed away and was brought to Istanbul so he could be buried in Yavuz Sultan Selim Mosque which was commissioned by Suleiman the Magnificent in loving memory of his father. Sultan Selim I who died at the age of 50 conquered and unified the Islamic holy lands. Protecting the lands in Europe, he gave priority to the East as he believed the real danger came from there.