The Ottoman Empire entered WWI with the attack on Russia's Black Sea coast on 29 October 1914. The attack prompted Russia and its allies, Britain and France, to declare war on the Ottoman Empire in November 1914. The Ottoman Empire was active in the Balkans theatre and Middle Eastern theatre – the latter had five main campaigns: the Sinai and Palestine Campaign, the Mesopotamian Campaign, the Caucasus Campaign, the Persian Campaign, and the Gallipoli Campaign. There were also several minor campaigns: the North African Campaign, the Arab Campaign and the South Arabia Campaign. There were several important Ottoman victories in the early years of the war, such as the Battle of Gallipoli and the Siege of Kut. The Armistice of Mudros was signed on 31 October 1918, ending the Ottoman participation in World War I.