How many times did large-scale population migrate to Sichuan in Qing Dynasty?

Sichuan has experienced seven great migrations in history. For the first time, after Qin destroyed Shu and Pakistan, thousands of Qin immigrants entered Shu, about 40,000 to 50,000. The second time, from the end of the Western Jin Dynasty, the population of northern China moved southward. During this period, a large number of immigrants from Shaanxi, Gansu and other places adjacent to Sichuan entered Sichuan from Qinling. The third time, in the early years of the Northern Song Dynasty, northerners moved south all over the country. At this time, Shaanxi and Gansu immigrants entered Sichuan; The fourth time was at the end of Yuan Dynasty and the beginning of Ming Dynasty, southern immigrants mainly from Hubei entered Sichuan. The fifth time, Yu Sheng immigrated to Sichuan in early Qing Dynasty. The largest number of immigrants this time were Hubei and Hunan (at that time, the administrative region was called "Huguang Province", and part of Guangxi was also under its jurisdiction), and the immigrant population reached more than 6.5438+0 million. Now the folklore "Huguang fills Sichuan" is a great migration when the blood and tears of Laochuan people are about to run out, which is a specific historical concept. The sixth time, War of Resistance against Japanese Aggression was liberated to the whole country in advance, and many people fled or "Nangan" settled in Sichuan; The seventh time was the Three Gorges immigrants from the end of 20th century to the beginning of 2nd/kloc-0th century, and many people settled in Sichuan.