The Persian campaign or invasion of Iran (Persian: اشغال ایران در جنگ جهانی اول) was a series of military conflicts between the Ottoman Empire, British Empire and Russian Empire in various area's of what was then neutral Qajar Iran, beginning in December 1914 and ending with the Armistice of Mudros on 30 October 1918, as part of Middle Eastern theatre of World War I. The fighting also involved local Persian units, who fought against the Entente and Ottoman forces in Iran. The conflict proved to be a devastating experience for Persia. Over 2 million Persian civilians died in the conflict, mostly due to the Armenian genocide by the Ottoman regime and Persian famine of 1917–1919, influenced by British and Russian actions. The Qajar government's inability to maintain the country's sovereignty during and immediately after the First World War led to a coup d'état in 1921 and Reza Shah's establishment of the Pahlavi dynasty.