After the Mondros Armistice, the majority of the Ottoman lands were shared among the victorious countries. Consequently, various defense fronts and resistance organizations started to appear in Anatolia and Thrace. The Turkish people needed to turn these resistance efforts into a movement of full independence, which could only be achieved under the leadership of Mustafa Kemal. When Mustafa Kemal landed in Samsun on May 19th, 1919 as the Inspector of the Army, the four year National War of Independence began. The circular issued in Amasya on June 22nd, 1919 was a call to, and declaration of, national liberation. This was followed by the Erzurum and Sivas congresses. In the Erzurum Congress, the Turkish people manifested its determination for national independence to the whole world as follows: “The lands of the motherland within the national boundaries is a whole, and cannot be partitioned. Mandates and patronages are unacceptable”.
The Entente States occupied İstanbul on March 16th, 1920 and dissolved the Ottoman Parliament. Some deputies were arrested, and some went to Ankara to join the Struggle for National Independence.
The Turkish Grand National Assembly (TGNA) was inaugurated on April 23rd, 1920 in Ankara and Mustafa Kemal was elected the President of the Assembly. This Assembly would henceforth conduct the Struggle for National Independence in the name of the nation. After the designated Mustafa Kemal Commander in Chief, war commenced against imperialist forces on all fronts. Meanwhile, on August 10th, 1920, the İstanbul Government signed the Treaty of Sevres which included very harsh provisions for the Turks.
Mustafa Kemal and the Ankara Government did not recognize the Treaty of Sevres. A struggle was started under the command of Kazım Karabekir in Eastern Anatolia, and this endeavor was concluded with success. As a result, the Gümrü Agreement was signed with Armenia on December 2nd, 1920. This was the first international agreement to which the TGNA was a party. The problems on the eastern front were completely resolved with the Moscow Treaty signed with Russia on 16th March, 1921 and the Kars Agreement signed with Armenia, Azerbaijan and Georgia on 13th October, 1921. On the western front, the Greek forces which occupied İzmir on May 15th, 1919 and started to advance in the Aegean region were driven back during the First and Second İnönü battles (January-April 1921), and they later suffered a crushing defeat in the Sakarya Pitch Battle (August-September 1921). Also, the French forces were pulled back from Adana and its environs in accordance with the Ankara Agreement (October 1921) signed with France. After that, all the forces and resources of the country were prepared for a general offensive to be carried out on the western front. The Greek forces were routed in the Grand Offensive and the Battle of the Commander-in-Chief (August 1922). İzmir was liberated on September 9th, 1922. This military success speeded up the process of establishing a new Republic. The Mudanya Armistice was signed between the Ankara Government and the Entente States (October 11th, 1922), and it was agreed that a conference would be held later in Lausanne to negotiate the provisions of the peace treaty. However, the additional invitation made by the Entente States to the İstanbul Government brought the sultanate to an end. The TGNA separated the Caliphate from the sultanate and abolished the sultanate on November 1st, 1922. Consequently, the last Ottoman Sultan Mehmet VI (Vahideddin) departed from İstanbul on November 17th, 1922.
The Lausanne Peace Treaty (July 24th, 1923): The Lausanne negotiations, in which the Ankara Government participated as the sole representative, commenced on November 21st, 1922. The Minister of Foreign Affairs İsmet Pasha (İnönü) presided over the Turkish delegation during negotiations which were suspended in February 1923, especially due to the disagreement over the future of capitulations. However, the talks resumed upon İsmet Pasha’s note dated April 23rd, 1923. The signing of the peace treaty comprising 143 articles, 17 annexes, protocols and declarations, concluded the National War of Independence. Thus, the TGNA Government was officially recognized, Turkey’s national borders were set, capitulations were lifted, the Ottoman debts were restructured, and consequently the political and economic independence and the right of sovereignty of Turkey were officially recognized. The treaty signed in Lausanne, Switzerland on July 24th, 1923, was ratified by the TGNA on August 23rd, 1923.