The United States census of 1850 was the seventh census of the United States.Conducted by the Census Office, it determined the resident population of the United States to be 23,191,876—an increase of 35.9 percent over the 17,069,453 persons enumerated during the 1840 census. The total population included 3,204,313 slaves. Although the official date of the census date was June 1, 1850, completed census forms indicate that the surveys continued to be made throughout the rest of the year.