Nanzhao (738 -937) was a slave regime in the southwest of China during the Tang Dynasty. Its territory included the whole of Yunnan today and parts of Guizhou, Sichuan, Tibet, Vietnam and Myanmar. It was founded in 738 by the leader of Meng Shezhao, Pelog, until it was destroyed by Duan Siping in 937 and Dali was established. Yunnan, in the southwest of China, is inhabited by ethnic groups with various names. The so-called "numerous species" in Biography of Two Heroes in the New Tang Dynasty is indeed true. According to legend, it was built by Zhuang. The State of Qin often opened a five-foot wide road from Shutong to Yunnan (Zhuge Liang began to widen the road). BC 109, Emperor Wu of the Han Dynasty sent general Guo Chang to destroy Yunnan and set up Yizhou County. Yongchang County (Zhibuwei, north of Baoshan County, Yunnan Province) was added in the Eastern Han Dynasty. Zhuge Liang pacified the south and added Xinggu (Malong County, Yunnan Province) and Xiangyun County, Yunnan Province. In 62 1 year, Tang Gaozu established Yaozhou (north of Yao 'an, Yunnan) and took charge of Jimmy for 32 years. In 632, Emperor Taizong established the Governor's Office in Rongzhou (bó Road, Yin Bo, southwest of Yibin County, Sichuan Province). During the reign of Emperor Xuanzong of the Tang Dynasty, the Governor's Department was in charge of 36 states and 137 counties, and later extended to 92 states. Liberation means coming and going as you please, without interfering with each other. This state of imprisonment is not conducive to backward ethnic groups, because the ruling class of the Han nationality can slowly extend its influence, resettle counties and counties, and force ethnic groups to gradually retreat. On the other hand, for example, at the end of the Southern Liang Dynasty, the rulers of the Liang Dynasty withdrew from Yunnan, and all the counties and counties were occupied by aristocratic chieftains, which was not conducive to the people of all ethnic groups, because it was a retrogression to restore the rule of aristocratic chieftains and expand the backward forces of counties and counties. During the Tianbao period of the Tang Dynasty, the Nanzhao State was established in Yunnan, which changed the above two unfavorable situations and greatly promoted the people of all ethnic groups. Nanzhao is a unified country with Wuman Mongol clan as the king and Baiman clan as the supplement, which is composed of all ethnic groups in China. A unified regime will naturally weaken Mr. Hao's scattered separatist forces; A country that integrates all ethnic groups will naturally abolish the fetters; To resist the strong neighbors of Tang and Tubo, it is natural to improve the country's economy and culture. After more than 500 years of rule in Nanzhao and Dali, the original backward appearance of the whole country has changed greatly, and the economy and culture have generally improved to the level of the Han nationality. Although some ethnic groups still maintain the so-called "old customs", compared with before the founding of Nanzhao, the number is not so much, and the level has also improved. Nanzhao and Dali once played a role in history, that is, they promoted the economic and cultural upgrading of backward ethnic groups to varying degrees.