Uryankhay Krai was the name of what is today Tuva and was a short-lived protectorate of the Russian Empire that was proclaimed on 17 April 1914, created from the Uryankhay Republic which had recently proclaimed its independence from the Qing dynasty of China in the Mongolian Revolution of 1911. After the February Revolution and abdication of Tsar Nicholas II, Uryankhay Krai recognized the new Russian Republic and reaffirmed its status as a Russian protectorate in 1917. During the Russian Civil War, the country was occupied by China and Russian "Whites" between 1918 and 1921. Supported by the Red Army, the Tuvan People's Revolutionary Party established the Soviet puppet state of the Tuvan People's Republic (initially Tannu Tuva) on 14 August 1921. The name Uryankhay is of Mongolian origin, and was the Russian exonym for Tuvans from the 17th century up through the early 20th century. The term was also the Tuvan endonym until the early 19th century, when they began referring to themselves as Tuvans, likely after a subgroup in the region. The protectorate's borders roughly correspond with that of the contemporary Russian Tuvan Republic. Much of Uryankhay Krai's territory was mountainous. The territory was bound by the Tannu-Ola mountains to the south, and the Sayan Mountains to the north. Tuva had been under the rule of the Qing dynasty since the mid-18th century. However, Russian settlers began immigrating en masse to the region in 1838 and 1839, following the discovery of gold deposits in the area. In subsequent years, Russians began constructing gold mines, and establishing a trading institutions in the region. Throughout the mid and late 19th century, a number of Russian scientists began documenting the region's native flora and studying the Tuvan people, and Russian settlers continued to immigrate to the region. Russian interest in the region continued through the early 20th century, and the Tsarist government sponsored a number of expeditions from 1906 through 1910 to locate mineral deposits in the area.