United States Census, 1890

The Eleventh United States Census was taken June 1, 1890. Unfortunately, most of the 1890 census was destroyed in 1921 during a fire in the basement of the Commerce Building in Washington, D.C. The 1890 census announced that the frontier region of the United States no longer existed and therefore the tracking of westward migration would no longer be tabulated in the census. This trend prompted Frederick Jackson Turner to develop his milestone Frontier Thesis.

The 1890 census was the first to be compiled on a tabulating machine, developed by Herman Hollerith. This introduction of technology reduced the time taken to tabulate the census from seven years for the 1880 census to two and a half years for the 1890 census. The total population of 62,622,250 was announced after only six weeks of processing. The public reaction to this tabulation was disbelief, as it was widely believed that the "right answer" was at least 75,000,000.

The logistical difficulties in compiling the census drove computing technology for the next fifty years until computers became widespread in industry. IBM's first electronic computer was created primarily to deal with the needs of the census in addition to military and academic uses.

This census is one of the three for which the original data is no longer available. Almost all the population schedules were damaged in a fire in 1921 and later destroyed by bureaucratic error. The Other Censuses that have lost almost all information were the 1800 and 1810 enumerations.