On 13 November 1918, the Occupation of Constantinople (present day Istanbul), the capital of the Ottoman Empire, occurred when French troops arrived, 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 de facto to the days following the Treaty of Lausanne. The occupation of Istanbul, along with the occupation of İzmir, contributed to the establishment of the Turkish national movement and led to the Turkish War of Independence.