1882 barred almost all Chinese from immigrating to the United States. Nonetheless, many Chinese immigrants arrived in America by obtaining false documents. The Chinese Exclusion Act allowed the Chinese Americans already settled in the United States to stay and provided for limited numbers of family members of Chinese Americans to immigrate with the correct paperwork. This loophole and the fateful 1906 earthquake that destroyed San Francisco's public records provided Chinese immigrants, almost entirely men, with the potential to immigrate with false documents stating their familial relationship to a Chinese American. These Chinese immigrants were called “paper sons,” because of their false papers. “Paper sons” relied on networks built by chain migration to buy documentation, develop strategies for convincing authorities on Angel Island of their legal status, and for starting a life in America. Immigrant gender ratios Single, young, male laborers were initially the largest group using chain migration to the United States in the nineteenth and early twentieth centuries. However, each immigrant group maintained a unique composition due to circumstances in home countries, goals of migration, and American immigration laws. For example, Irish migration after 1880 had a 53.6% female majority, the only migrant group with that distinction. Irish men and women faced economic crisis, overpopulation, and problematic inheritance laws for large families, thereby compelling many of Ireland's daughters to leave with its sons. Italian chain migration was initially wholly male based on intent to return, but became a source of family reunification when wives eventually immigrated. Chinese chain migration was almost exclusively male until 1946, when the War Brides Act allowed Chinese wives of American citizens to immigrate without regard to Chinese immigration quotas. Before that time, chain migration was limited to “paper sons” and actual sons from China. The imbalanced sex ratio of Chinese immigrants was due to Chinese exclusion laws and the inability to bring current wives or to marry and return to the United States, inhibiting the corrective measure of chain migration. When immigrant groups react to economic pull factors in labor markets, chain migration via family has been used informally to balance out the gender ratio in ethnic immigrant communities. Advertisements It was common in the nineteenth and early twentieth centuries for companies and even states to advertise to potential European immigrants in their home countries. These advertisements in magazines and pamphlets made information available for immigrants to find travel and decide where to settle