The first U.S. census, conducted in 1790, recorded a population of 3,929,214 people.
The census counted residents as of August 2, 1790, just after the new federal government began operating under the Constitution. Article I, Section 2 required an enumeration for congressional representation, making the census both a population count and a constitutional process.
Federal marshals, rather than a permanent census bureau, conducted the enumeration. The law divided people into categories that distinguished free people, enslaved people, and other residents. The schedules were compiled by state and sent to President George Washington.
Virginia was the most populous state, with 747,610 residents, while Delaware was the least populous, with 59,094. The total excluded some Native Americans living outside the taxed or surveyed population and therefore was not a complete count of everyone living in the territory. Later censuses were held every ten years, a pattern that continues today.