The 1920 census includes all fifty U.S. states and territories, as well as Military and Naval Forces, the Virgin Islands, Puerto Rico, and for the first time American Samoa, Guam, and the Panama Canal Zone.
The 1920 Census was begun on 1 January 1920. The actual date of the enumeration appears on the heading of each page of the census schedule, but all responses were to reflect the individual's status as of 1 January, even if the status had changed between 1 January and the day of enumeration. For example, children born between 1 January and the day of enumeration were not to be listed, while individuals alive on 1 January but deceased when the enumerator arrived were to be counted.
The following questions were asked by enumerators:
Due to boundary modifications in Europe resulting from World War I, some individuals were uncertain about how to identify their national origin. Enumerators were instructed to spell out the name of the city, state, province, or region of respondents who declared that they or their parents had been born in Germany, Austria-Hungary, Russia, or Turkey. Interpretation of the birthplace varied from one enumerator to another. Some failed to identify specific birthplaces within those named countries, and others provided an exact birthplace in countries not designated in the instructions.
There are no separate Indian population schedules in the 1920 census. Inhabitants of reservations were enumerated in the general population schedules. Enumerators were instructed not to report servicemen in the family enumerations but to treat them as residents of their duty posts. The 1920 census includes schedules for overseas military and naval forces.
Taken from Chapter 5: Research in Census Records, The Source: A Guidebook of American Genealogy by Loretto Dennis Szucs; edited by Loretto Dennis Szucs and Sandra Hargreaves Luebking (Salt Lake City, UT: Ancestry Incorporated, 1997).