The history of Yerevan dates back to the 8th century BC, with the founding of the fortress of Erebuni in 782 BC by king Argishti I at the western extreme of the Ararat plain. Erebuni was "designed as a great administrative and religious centre, a fully royal capital." By the late ancient Armenian Kingdom, new capital cities were established and Yerevan declined in importance. Under Iranian and Russian rule, it was the center of the Erivan Khanate from 1736 to 1828 and the Erivan Governorate from 1850 to 1917, respectively. After World War I, Yerevan became the capital of the First Republic of Armenia as thousands of survivors of the Armenian Genocide in the Ottoman Empire arrived in the area. The city expanded rapidly during the 20th century as Armenia became part of the Soviet Union. In a few decades, Yerevan was transformed from a provincial town within the Russian Empire to Armenia's principal cultural, artistic, and industrial center, as well as becoming the seat of national government.