The nominal head of the early censuses was the secretary of state, but management responsibility was actually devolved to the U.S. marshal in each state. These marshals collected and tabulated their own returns; the secretary of state only oversaw the final compilation and tabulation of the data.
By 1840, the increasing standardization of census questionnaires and the increasingly complicated process of conducting the census made it clear that more leadership at the federal level was necessary. Secretary of State John Forsythe appointed William Augustus Weaver as the first "superintending clerk of the census" in that year. Weaver and his successors oversaw the technical aspects of the census, including designing questionnaires, and more closely managed the tabulation process.
By 1870, the leader of the Census Office was the "superintendent of the census." The superintendent oversaw the entire census-taking process, and usually held the position from a year before the census until the final tabulations had been published.
After the Census Office became a permanent agency in 1902, the first director was the incumbent superintendent, William Rush Merriam. He set the standard for many directors of the U.S. Census Bureau over the next hundred years by focusing on external issues such as congressional testimony and leaving technical operations to the experts.