that's what i learned when i was in turkey in any case. wikipedia, for what it's worth, seems to agree:
Following years of decline, the Ottoman Empire entered World War I through the Ottoman-German Alliance in 1914, and was ultimately defeated. After the war, the victorious Allied Powers sought the dismemberment of the Ottoman state through the Treaty of Sèvres.
The occupation of İstanbul and İzmir by the Allies in the aftermath of World War I prompted the establishment of the Turkish national movement.[5] Under the leadership of Mustafa Kemal Pasha, a military commander who had distinguished himself during the Battle of Gallipoli, the Turkish War of Independence was waged with the aim of revoking the terms of the Treaty of Sèvres. By September 18, 1922, the occupying armies were repelled and the country saw the birth of the new Turkish state. On November 1, the newly founded parliament formally abolished the Sultanate, thus ending 623 years of Ottoman rule. The Treaty of Lausanne of July 24, 1923, led to the international recognition of the sovereignty of the newly formed "Republic of Turkey" as the successor state of the Ottoman Empire, and the republic was officially proclaimed on October 29, 1923, in the new capital of Ankara.
Mustafa Kemal became the republic's first president and subsequently introduced many radical reforms with the aim of founding a new secular republic from the remnants of its Ottoman past. According to the Law on Family Names, the Turkish parliament presented Mustafa Kemal with the honorific name "Atatürk" (Father of the Turks) in 1934.