The Treaty of Lausanne was a peace treaty signed in Lausanne, Switzerland on 24 July 1923, that settled the Anatolian and East Thracian parts of the partitioning of the Ottoman Empire. The treaty of Lausanne was ratified by the Greek government on 11 February 1924, by the Turkish government on 31 March, and by the governments of Great Britain, Italy and Japan on 6 August. It was registered in the League of Nations Treaty Series on 5 September 1924. The Treaty of Lausanne superseded the Treaty of Sèvres which was signed by representatives of the Ottoman Empire.
The treaty was the consequence of the Turkish War of Independence between the Allies of World War I and the Ankara-based Grand National Assembly of Turkey (Turkish national movement) led by Mustafa Kemal Atatürk. The treaty also led to the international recognition of the sovereignty of the new Republic of Turkey as the successor state of the defunct Ottoman Empire.