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 Caliphate
The Turkish national movement, as the details explained in Turkish War of Independence, formed a Turkish Grand National Assembly, and secured formal recognition of the nation's independence and new borders on July 24, 1923 through the Treaty of Lausanne. The National Assembly declared Turkey a republic on October 29, 1923, and proclaimed Ankara its new capital. After over 600 years, the Ottoman Empire had officially ceased to exist. However, under Allied direction, the Sultan pledged to suppress such movements and secured an official fatwa from the Sheikh ul-Islam declaring them to be un-Islamic. But the nationalists steadily gained momentum and began to enjoy widespread support. Many sensed that the nation was ripe for revolution. In an effort to neutralize this threat, the Sultan agreed to hold elections, with the hope of placating and co-opting the nationalists. To his dismay, nationalist groups swept the polls, prompting him to again dissolve parliament in April 1920.