The Ottoman Empire
The Ottoman Empire was a multi-ethnic state that existed from 1299 to 1761, one of the largest empires to rule the borders of the Mediterranean Sea. At the height of its power, it included Anatolia, the Middle East, most of The Moorish Kingdoms, Iberia, Austria, and The Kingdom of Two Sicilies. It was established by a tribe of Oghuz Turks in western Anatolia and ruled by the Osmanli dynasty. In diplomatic circles it was often referred to as the Sublime Porte or simply as the Porte, from the French translation of the Ottoman name Bâb-i-âlî "high gate", due to the greeting ceremony the Sultan held for foreign ambassadors at the Palace Gate. This has also been interpreted as referring to the Empire's position as gateway between Europe and Asia. In its day, the Ottoman Empire was also commonly referred to as the Turkish Empire or Turkey.
Early History OTL
The Ottoman Empire was founded by Osman I from the remnants of the Sultanate of Rum. After being devastated by the Mongol invasion of 1320 and the long dominance of Timur the Lame, the Ottomans destroyed the Byzantine Empire or what was left of it by 1453. Then the Ottomans began moving quickly through all of The Middle East, Europe, and Central Asia.
The European War
Under Mehmed II The Conqueror, the Ottoman Empire invaded modern (not OTL) Iberia, which was then being fought over by the Spanish Warring Factions. They conquered it very quickly in only 10 years. The Ottomans attacked The Italian States only a short time later, and by 1641 was besieging Rome. They were also invading Austria and destroyed Moscovy at the same time. Soon after they united with Isfahan Persia to combat the European resistance. By that time The West Europa Alliance was created to destroy the Muslim threat to the world. However the united Muslim armies proved to powerful at the Battle of Vennia. The sultan decided not to expand any farther with the Battle of Vennia being a pyrrhic victory to the Ottomans and so strong forts were put up around the border of the empire.