The Occupation of Constantinople

British Warships in the Bosphorus: HMS Ajax and
HMS Ramillies and Three Destroyers

The Occupation of Constantinople (present-day Istanbul) was the occupation of the capital of the Ottoman Empire, following the Armistice of Mudros by the Triple Entente of World War I. The first French troops entered the city on 12 November 1918, followed by British troops the next day. The occupation had two stages: the de facto stage from 13 November 1918 to 20 March 1920, and the de jure stage from 20 March 1920 to the days following the Treaty of Lausanne. 

Scottish Soldiers of the 28th Division in Constantinople

The city was divided into zones of occupation: the Galata and Pera districts were under British responsibility, the old city and southwest under French, and Üsküdar (Scutari) on the Anatolian side was under Italian control.  The occupation along with the occupation of İzmir, mobilized the establishment of the Turkish national movement and the Turkish War of Independence.

Sources: The World History Project