Orūmīyeh, city, capital of West Āz̄arbāyjān province, northwestern Iran. It lies just west of Lake Urmia on a large fertile plain that yields grains, fruits, tobacco, and other crops. The population is mainly Azeri and Kurdish, with Assyrian and Armenian minorities. The remains of ancient settlements are scattered over the plain, as are traces of the ancient kingdom of Urartu.
The city was long an area of contention between the Ottoman and Persian empires, and it was occasionally occupied by Russia from 1911 until the Russian Revolution (1917). Assyrian and Armenian Christians formed nearly half the population in 1900, but in 1918 many fled after the retreat of Russians from the area. Most of the remainder were massacred. Some survivors were later repatriated by the Iranian government.
Orūmīyeh is connected by primary roads with Tabrīz, 75 miles (120 km) northeast, and with Kermānshāh, 250 miles (400 km) southeast. There is an airfield nearby. Pop. (2011) 667,499; (2016) 736,224.