During the 16th and 17th centuries, in particular at the height of its power under the reign of Suleiman the Magnificent, the Ottoman Empire was a multinational, multilingual empire controlling much of Southeast Europe, Western Asia, the Caucasus, North Africa, and the Horn of Africa. At the beginning of the 17th century the empire contained 32 provinces and numerous vassal states. Some of these were later absorbed into the Ottoman Empire, while others were granted various types of autonomy during the course of centuries.[dn 4]

Under the reign of who did the Ottoman empire control much of Southeastern Europe?