Why do ethnic minorities immigrate to Nanjing?

The migration of ethnic minorities to Nanjing is a major ethnic migration caused by the horse race in history. After the development of the Six Dynasties, Nanjing's population reached one million, making it the first city in the world with a population of over one million. The minority population is about135,000, and the Hui population is basically registered population. Among the 56 ethnic groups registered in Nanjing, there are 53, and the Hui nationality has the largest population of ethnic minorities in Nanjing.