The first population summit of Chinese history appeared in the Han Dynasty. The general population of Eastern Han slightly reduced than those in Western Han while population increased rapidly in the four prefectures of Hunan district where the number of households was one percent of the whole population in Western Han but it rose to 6.7 percent in Eastern Han and the number of population rose from 1.2 to 5.7 percent. The main causes of population increase are listed following: the grate immigrants, the exploitation of Hunan district, the devel...