The Ottoman Empire (/ˈɒtəmən/; Ottoman Turkish: دَوْلَتِ عَلِيّهٔ عُثمَانِیّه‎ Devlet-i Aliyye-i Osmâniyye, Modern Turkish: Osmanlı İmparatorluğu or Osmanlı Devleti), also known as the Turkish Empire, Ottoman Turkey or Turkey, was an empire founded in 1299 by Oghuz Turks under Osman I in northwestern Anatolia. After conquests in the Balkans by Murad I between 1362 and 1389, the Ottoman sultanate was transformed into a transcontinental empire and claimant to the caliphate. The Ottomans ended the Byzantine Empire with the 1453 conquest of Constantinople by Mehmed the Conqueror. 

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]
Who was it founded by?
 After conquests in the Balkans by Murad