Treaty of Lausanne (1923)

Key provisions

• Borders and sovereignty: The treaty fixed the land and sea frontiers of Turkey in Anatolia and Eastern Thrace, ending most Ottoman territorial claims and defining the limits of Turkish jurisdiction.
• Population exchange: It formalized a compulsory exchange of Greek Orthodox and Muslim populations between Greece and Turkey, with specific exceptions for certain urban or island communities.
• Minorities and protections: Non-Muslim minorities remaining in Turkey were afforded certain protections and legal recognition; the arrangement aimed to settle communal status questions left from the Ottoman period.
• Economic and legal measures: The capitulations (special privileges for foreign nationals) granted under the Ottoman Empire were abolished and financial claims were negotiated between the parties.
• Straits and international regimes: The treaty addressed the regime of the Turkish Straits, subject to later modification by subsequent agreements.

Lausanne was negotiated and signed by representatives of Turkey and the principal Allied powers and neighboring states. In addition to Turkey and Greece, signatories or participants included Italy, France, the United Kingdom, Japan and the Kingdom of Yugoslavia. The conference reflected the shift in power after World War I and the practical authority of Turkish national forces under Mustafa Kemal (Atatürk).

Consequences were profound: the treaty gave international recognition to the Republic of Turkey, settled many legal and territorial questions that ended the Ottoman imperial order, and created a framework for population and minority arrangements. However, it did not eliminate all disputes. Ownership and control of numerous Aegean islets, maritime boundaries and access rights in the Aegean Sea have remained sources of tension between Greece and Turkey and led to crises in later decades.

Today the Treaty of Lausanne remains a cornerstone of Turkish foreign relations and regional law. Its provisions continue to be cited in diplomatic negotiations and legal arguments concerning borders, minority rights and maritime jurisdiction, while some aspects were adjusted by later conventions and agreements as circumstances changed in the twentieth century.