The USGenWeb Census Project Intro to Federal Census Research 1820 Census Facts Series: M33 Rolls: 1 - 142.

Fourth U.S. decennial population census. U.S. population: 9.6 million (8.1 million free, 1.5 million slave) Census conducted by U.S. marshals under the direction of the Secretary of State. Census day: 1st Monday in August (7 August 1820). Mandated copies: One set, sent to the federal district court. Same copy ordered sent to the U.S. Secretary of State in 1830. Information Provided on 1820 Census: Name of family head age sex race foreigners not naturalized slaves industry (agriculture, commerce, and manufactures).

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