Birth certificates may have existed for some people before the Census Bureau was established in 1902, but the most common records prior to the 1930s were marriage and baptism records maintained by churches and census records.

History of the birth certificate: from inception to the future of electronic data

There was no census conducted for non-citizens, such as Native Americans, and some tribal nations may have kept separate records.

Oklahoma Historical Society

African Americans became citizens in 1879 with the 13th amendment.

Native Americans were non-citizens until June 2nd, 1924, and civil rights were not granted until 1969, so many natives born before the 1970s are undocumented.

On this day, all American Indians made United States citizens

Asians could not be US citizens until 1952.

The Immigration and Nationality Act of 1952 (The McCarran-Walter Act)

Citizenship prior to written records was determined mostly by examining skin color and facial characteristics because of this:

1790 NATURALIZATION ACT Excluded non-white people from eligibility to naturalize. Naturalization requirements included two years of residence in the country and “good moral character,” and an applicant must be a “free white person.” The Naturalization Act of 1795 extended the residency requirement to five years. In 1798, this was extended to 14 years, then back to five in 1802.