The 1790 United States census recorded a population of 3,929,214 people.
It was the first census conducted under the new Constitution. Census Day was August 2, 1790, and Congress assigned the work mainly to U.S. marshals supervising local assistants. Enumerators visited households and recorded population categories established by federal law rather than collecting the detailed demographic information used by modern censuses.
The total covered the states that had joined the Union by then, along with districts and territories counted under federal authority. Virginia was the most populous state, with 747,610 people, while Delaware was the least populous state, with 59,094. The census was published in 1791 and ran to 56 pages.
George Washington and Secretary of State Thomas Jefferson both suspected that the count was too low. Travel difficulties, scattered settlements, limited administrative resources, and people being missed or refusing to participate all affected the result. Even with those limitations, the census created the first official population baseline for the United States.