The 1790 United States census counted 3,929,214 people in the entire country.
It was the first census conducted under the new Constitution. Census Day was August 2, 1790, and federal law assigned the work mainly to U.S. marshals supervising local enumeration. The count covered the states then in the Union and certain territories under federal administration.
Virginia was the most populous state, with 747,610 people, while Delaware was the least populous, with 59,094. The census counted free people and enslaved people under categories established by the constitutional apportionment system. Enslaved people were counted as three-fifths for representation and direct taxation, not as three-fifths of a person in the population total.
George Washington and Thomas Jefferson both suspected that the results undercounted the actual population. The schedules were published in 1791 in a 56-page report, and the census cost $44,377.28.