Persian campaign (World War I)

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 areas 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 the 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.

Source: Wikipedia — Persian campaign (World War I) (CC BY-SA 4.0)