By the 19th century , the empire began to decline when ethno-nationalist uprisings occurred across the empire . Thus , the last quarter of the 19th and the early part of the 20th century saw some 7 – 9 million Muslim refugees ( Turks and some Circassians , Bosnians , Georgians , etc. ) from the lost territories of the Caucasus , Crimea , Balkans , and the Mediterranean islands migrate to Anatolia and Eastern Thrace . By 1913 , the government of the Committee of Union and Progress started a program of forcible Turkification of non-Turkish minorities . By 1914 , the World War I broke out , and the Turks scored some success in Gallipoli during the Battle of the Dardanelles in 1915 . During World War I , the government of the Committee of Union and Progress continued with its Turkification policies , which affected non-Turkish minorities , such as the Armenians during the Armenian Genocide and the Greeks during various campaigns of ethnic cleansing and expulsion . In 1918 , the Ottoman Government agreed to the Mudros Armistice with the Allies
various campaigns of ethnic cleansing and expulsion
Greek genocide
Turkish people