July 24, 1923

Treaty of Lausanne

Turkey and the Allied powers sign the Treaty of Lausanne

The treaty famous for settling modern Turkey's borders deliberately left one of them out — the frontier with Iraq, and the Mosul question with it.

24 July 1923, at the Palais de Rumine

On 24 July 1923, plenipotentiaries signed a peace treaty at Lausanne between Turkey and the British Empire, France, Italy, Japan, Greece, Romania and the Serb-Croat-Slovene State — eight contracting polities named in the preamble, across 143 articles. İsmet Pasha signed for the Government of the Grand National Assembly of Turkey.

Sir Horace Rumbold signed for the British Empire. Lord Curzon, the statesman most associated with the negotiations, had led the British delegation during the earlier conference phase but was not the principal British signer that day.

What it fixed, and what it postponed

The treaty fixed Turkey's frontiers with Bulgaria and Greece and recognized its Syrian frontier. The parties accepted Turkish sovereignty within those frontiers, Turkey renounced rights outside them, and Article 28 abolished the capitulations.

The Turkey–Iraq frontier was left to later British-Turkish negotiations, with nine months allowed. The compulsory Greek-Turkish population exchange was not made here either — that convention had been signed on 30 January 1923, and the peace treaty gave it the same legal force as if incorporated.

Signed under one government, in force under another

The delegates also signed or issued instruments covering the Straits, amnesty, economic and judicial matters, and the evacuation of Allied-occupied Turkish territory. The amnesty declaration still allowed Turkey to exclude 150 named people from the country.

Article 1 made the definitive re-establishment of peace conditional on entry into force after ratification, which came on 6 August 1924. The Republic of Turkey did not exist on the day Turkey signed — it was proclaimed on 29 October 1923.

Sources

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How this was checked

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What the sources leave uncertain

The signature date and place are secure.
Descriptions saying the treaty fixed all boundaries of modern Turkey are too broad. Article 3 expressly deferred the Iraq frontier—and the Mosul question—to later negotiations and possible League of Nations action.
The treaty was signed by the Government of the Grand National Assembly. The Republic of Turkey was not proclaimed until 29 October 1923.
The Ottoman Empire’s endpoint can be framed in several political and legal ways, but the sultanate and Ottoman monarchy had already been abolished on 1 November 1922.