Outer Mongolia was the name of a territory in the Manchu-led Qing dynasty of China from 1691 to 1911. It corresponds to the modern-day independent state of Mongolia and the Russian republic of Tuva. The historical region gained de facto independence from Qing China during the Xinhai Revolution.

The Qing dynasty, officially the Great Qing, was a Manchu-led imperial dynasty of China and the last imperial dynasty in Chinese history. The dynasty, proclaimed in Shenyang in 1636, seized control of Beijing in 1644, which is considered the start of the dynasty's rule. The dynasty lasted until 1912, when it was overthrown in the Xinhai Revolution. In Chinese historiography, the Qing dynasty was preceded by the Ming dynasty and succeeded by the Republic of China. The multi-ethnic Qing dynasty assembled the territorial base for modern China. It was the largest imperial dynasty in the history of China and in 1790 the fourth-largest empire in world history in terms of territorial size. With over 426 million citizens in 1907, it was the most populous country in the world at the time.