Decline and modernization of the Ottoman Empire
Beginning from the late eighteenth century, the Ottoman Empire faced challenges defending itself against foreign invasion and occupation. In response to foreign threats, the empire initiated a period of tremendous internal reform which came to be known as the Tanzimat, which succeeded in significantly strengthening the Ottoman central state, despite the empire's precarious international position. Over the course of the nineteenth century, the Ottoman state became increasingly powerful and rationalized, exercising a greater degree of influence over its population than in any previous era. The process of reform and modernization in the empire began with the declaration of the Nizam-ı Cedid (New Order) during the reign of Sultan Selim III and was punctuated by several reform decrees, such as the Hatt-ı Şerif of Gülhane in 1839 and the Hatt-ı Hümayun in 1856. At the end of this period, marked with 1908, to a degree the Ottoman military became modernized and professionalized according to the model of Western European Armies. The period was followed by the defeat and dissolution of the Ottoman Empire (1908–1922).
Ottoman Empire
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.
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, western Kurdistan, and Western Georgia (incl. western Samtskhe) fell into Ottoman hands, while southern Dagestan, Eastern Armenia, Eastern Georgia, and Azerbaijan remained Persian.