Wei Yuan
The Dzungar (or known as Zunghar), Oirat Mongols who lived in an area that stretched from the west end of the Great Wall of China to present-day eastern Kazakhstan and from present-day northern Kyrgyzstan to southern Siberia (most of which is located in present-day Xinjiang), were the last nomadic empire to threaten China, which they did from the early 17th century through the middle of the 18th century. After a series of inconclusive military conflicts that started in the 1680s, the Dzungars were subjugated by the Manchu-led Qing dynasty (1644–1911) in the late 1750s. According to Qing scholar Wei Yuan, 40 percent of the 600,000 Zunghar people were killed by smallpox, 20 percent fled to Russia or sought refuge among the Kazakh tribes and 30 percent were killed by the Qing army of Manchu Bannermen and Khalkha Mongols.