It looks like you're using Internet Explorer 11 or older. This website works best with modern browsers such as the latest versions of Chrome, Firefox, Safari, and Edge. If you continue with this browser, you may see unexpected results.
provides questionnaires and instructions, plus individual histories of each census. Pages 119-124 provide tables showing the "Population Items on Principal Census Questionnaires: 1790-2000."
"contains facsimile copies of the enumeration forms used in the decennial census of the United States from 1860 through 2000, and the American Community Survey (2000+)."
Map Guide to the U.S. Federal Censuses, 1790-1920 by William Thorndale & William Dollarhide
provides "a Longitudinal Tract Data Base (LTDB), which provides public-use tools to create estimates within 2010 tract boundaries for any tract-level data (from the census or other sources) that are available for prior years as early as 1970."