Bachelor society was considered a form of social organization peculiar to Chinese immigrants in North America. From the mid-nineteenth century to World War II, white politicians and social critics characterized Chinese in the United States and Canada as inscrutable aliens living in mysterious clan networks of single men. Nineteenth-century political morality and twentieth-century sociology established the chief features of bachelor society: single male workers, female prostitutes, and transient life. In nineteenth-century travelogues and political commentary, the image of bachelor life was that of dissolute men trapped in a culture of vice, which included frequenting opium dens, gambling houses, and brothels. Critics of Chinese immigration observed the absence of nuclear families as evidence that Chinese men had no commitment to permanent residence and assimilation to North American societies.