Naturalization Information in U.S. Census Schedules 1820 Foreigners not naturalized 1830 Aliens, Foreigners not naturalized 1870 Column 19 - Male citizens of U.S. 21 years of age and upwards Column 20 - Male citizens of U.S. 21 years of age and upwards where right to vote is denied on other grounds than rebelling or other crime 1900 Column 18 - Naturalization 1910 Column 16 - Whether naturalized or alien 1920 Column 14 - Naturalized or alien Column 15 - If naturalized, year of naturalization 1930 Column 23 - Naturalized or alien Abbreviations used in census records relating to naturalization AL - Individual was still an alien and had not begun the naturalization process. PA - The individual had filed his “first papers,” also known as declaration of intention. NA - A naturalized citizen, the individual had completed the naturalization process.