<P> Sultan Selim I (1512--1520) dramatically expanded the Empire's eastern and southern frontiers by defeating Shah Ismail of Safavid Persia, in the Battle of Chaldiran . Selim I established Ottoman rule in Egypt, and created a naval presence on the Red Sea . After this Ottoman expansion, a competition started between the Portuguese Empire and the Ottoman Empire to become the dominant power in the region . </P> <P> Suleiman the Magnificent (1520--1566) captured Belgrade in 1521, conquered the southern and central parts of the Kingdom of Hungary as part of the Ottoman--Hungarian Wars, and, after his historic victory in the Battle of Mohács in 1526, he established Turkish rule in the territory of present - day Hungary (except the western part) and other Central European territories . He then laid siege to Vienna in 1529, but failed to take the city . In 1532, he made another attack on Vienna, but was repulsed in the Siege of Güns . Transylvania, Wallachia and, intermittently, Moldavia, became tributary principalities of the Ottoman Empire . In the east, the Ottoman Turks took Baghdad from the Persians in 1535, gaining control of Mesopotamia and naval access to the Persian Gulf . In 1555, the Caucasus became officially partitioned for the first time between the Safavids and the Ottomans, a status quo that would remain until the end of the Russo - Turkish War (1768--74). By this partitioning of the Caucasus as signed in the Peace of Amasya, Western Armenia, and Western Georgia fell into Ottoman hands, while southern Dagestan, Eastern Armenia, Eastern Georgia, and Azerbaijan remained Persian . </P> <P> France and the Ottoman Empire, united by mutual opposition to Habsburg rule, became strong allies . The French conquests of Nice (1543) and Corsica (1553) occurred as a joint venture between the forces of the French king Francis I and Suleiman, and were commanded by the Ottoman admirals Barbarossa Hayreddin Pasha and Turgut Reis . A month before the siege of Nice, France supported the Ottomans with an artillery unit during the 1543 Ottoman conquest of Esztergom in northern Hungary . After further advances by the Turks, the Habsburg ruler Ferdinand officially recognized Ottoman ascendancy in Hungary in 1547 . </P> <P> In 1559, after the first Ajuran - Portuguese war, the Ottoman Empire would later absorb the weakened east African Adal Sultanate into its domain . This expansion furthered Ottoman rule in Somalia and the Horn of Africa . This also increased its influence in the Indian Ocean to compete against the Portuguese with its close ally the Ajuran Empire . </P>

When did the ottoman empire reached its peak