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.
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.