By 18 September 1922 the Greek, Armenian and French armies had been expelled, and the Turkish Provisional Government in Ankara, which had declared itself the legitimate government of the country on 23 April 1920, started to formalise the legal transition from the old Ottoman into the new Republican political system. On 1 November 1922, the Turkish Parliament in Ankara formally abolished the Sultanate, thus ending 623 years of monarchical Ottoman rule. The Treaty of Lausanne of 24 July 1923, which superseded the Treaty of Sèvres, led to the international recognition of the sovereignty of the newly formed "Republic of Turkey" as the successor state of the Ottoman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 29 October 1923 in Ankara, the country's new capital. The Lausanne Convention stipulated a population exchange between Greece and Turkey, whereby 1.1 million Greeks left Turkey for Greece in exchange for 380,000 Muslims transferred from Greece to Turkey.