What was the population of the US according to the first census?
1790 United States Census
Congress assigned responsibility for the 1790 census to the marshals of United States judicial districts under an act which, with minor modifications and extensions, governed census taking until the 1840 census. "The law required that every household be visited, that completed census schedules be posted in 'two of the most public places within [each jurisdiction], there to remain for the inspection of all concerned...' and that 'the aggregate amount of each description of persons' for every district be transmitted to the president."[2]