Yunnan is a province of the People's Republic of China, located in the far southwest of the country. It spans approximately 394,000 square kilometres (152,000 sq mi) and has a population of 45.7 million (2009). The capital of the province is Kunming, formerly also known as Yunnan. The province borders Vietnam, Laos, Burma.
Yunnan is situated in a mountainous area, with high elevations in the northwest and low elevations in the southeast. Most of the population lives in the eastern part of the province. In the west, the altitude can vary from the mountain peaks to river valleys as much as 3,000 metres (9,800 ft). Yunnan is rich in natural resources and has the largest diversity of plant life in China. Of the approximately 30,000 species of higher plants in China, Yunnan has perhaps 17,000 or more. Yunnan's reserves of aluminium, lead, zinc and tin are the largest in China, and there are also major reserves of copper and nickel.
Yunnan became part of the Han Empire during the 2nd century BC. It became the seat of a Tibeto-Burman-speaking kingdom of Nanzhao in the 8th century AD. Nanzhao was multi-ethnic, but the elite most likely spoke a northern dialect of Yi. The Mongols conquered the region in the 13th century, with local control exercised by warlords until the 1930s. Ethnic minorities in Yunnan account for about 34 percent of its total population. Major ethnic groups include Yi, Bai, Hani, Zhuang, Dai and Miao. The provincial capital is Kunming.
--Introduction from wikipedia