Imperial Household Department
The number of booi aha of the Imperial Household Department seems to have risen mainly during the Nurhaci's conquest of the eastern fringes of the Liao River basin in the 1610s and 1620s, resulting in the massive increase of the numbers of captives. In 1618, Nurhaci increased the Jurchen state's population by 300,000 by the taking of Fu-shun. This large increase of its population changed the policy on booi aha. During the first year of conquest (to 1624), the captured Chinese were generally enslaved, and bore obligations to private persons, while later (in 1624–1625) they were often enrolled in the ranks of the semi-dependent agriculture class, jusen, who bore obligations to the state. Freeholder status was given to Li Yongfang's 1,000 troops after his surrender of Fushun, and the later Chinese Bannermen (Hanjun, or Han Bannermen) Bao Chengxian and Shi Tingzhu also experience good fortune in Qing service after their surrenders in 1622 at Guangning.