The U.S. Census: History of the U.S. Census

U.S. Census data and methodology have changed over time from the first census of the U.S. in 1790. Changes include:  

• Enumeration methods
• Demographic/racial categories
• Number and types of questions asked
• Non-population schedules added
• Tabulation technology

This page will highlight important dates in the development of the census, along with specific historical context and changes to the census that researchers should become familiar with.

The questions asked and data collected on the Census population questionnaires changed over time.  In looking at original images of the population census, researchers may encounter difficulty deciphering the structure and categories of the original form. In other cases, databases such as Ancestry.com may provide printer-friendly views of the Census pages, only showing a portion of the data.

If you would like to be able to see a copy of the structure and questions on a census form for a particular decennial census, you can find these in PDF format online through the National Archives and Records Administration (NARA).  See the links below to access these views by year. The PDF will show all of the information/categories that were included on the form for a particular year. 

Some states also held their own censuses.  North Carolina had its own special census from 1784-1787.  The only counties included were: Bertie, Burke, Camden, Carteret, Caswell, Chatham, Chowan, Currituck, Duplin, Gates, Granville, Halifax, Hyde, Johnston, Jones, Martin, Montgomery, New Hanover, Northampton, Onslow, Pasquotank, Perquimans, Pitt, Richmond, Sullivan (now in TN), Surry, Tyrell, Warren, and Wilkes.

• State census of North Carolina, 1784-1787, transcribed and indexed by Alvaretta Kenan Register. Baltimore, Md.: Genealogical Pub. Co., 2001.

Learn more:

• U.S. Census Bureau History: State Censuses

The Census has undergone significant change from the first census in 1790. Knowing when significant changes were made in enumeration methods can help researchers understand what information they will find and will not find and how to interpret records and data.  Several key dates are listed below.  To learn more about Census history, visit the U.S. Census Bureau's "Agency History" pages and click on the image to the right to explore a graphical timeline of U.S. Census history for the U.S. Census Bureau.
 

1790:  The first U.S. Census was in 1790 and only recorded names of the head of the household.  Everyone else in the household was simply tallied by age, gender, and race.

1790-1840:  Only heads of the household were listed by name for white and free black families with a column that indicated the number of slaves in the household.

1850:  All free people in a household appear by name.

1870:  Formerly enslaved people emancipated after the Civil War appear by name for the first time.  Before then, they appear only as tallies by age and gender in the slave schedules.  Between 1870-1880, it’s not uncommon for newly freed slaves to change their last name.

1880:  The relationship of an individual to the head of household is included.

1890:  Most of the Census was destroyed by fire, only fragments remain.  For more information see National Archives Prologue, Spring 1996, Vol. 28, No. 1.

1940:  Sampling began, meaning additional questions were asked of about 5% of the population (two people per page).

1950:  Shows the April 1, 2022 release of names. Every sixth person was sampled, or asked additional questions.

Here are definitions of terms you may encounter while conducting census research. 

Enumeration - The actual counting of the people.

Enumerator - A census worker who did the counting for the census and went door to door.

Enumeration District - The area each enumerator was assigned to. 

Non-population Schedules - Sections of the census other than the population schedule, such as the agricultural, industry and manufacturers, mortality, slave schedules, veterans schedule, etc. that can detail information about specific populations and trades.  These were all taken during certain time periods in census history.  They can be useful to look at if your ancestor was involved in that particular grouping.

Population Schedule - This is the largest and most well known U.S. Census Bureau program where the population is counted and surveyed in years ending with "0."  Article I of the Constitution requires that a census be taken every ten years for the purpose of reapportioning the U.S. House of Representatives. Title 13 of the U. S. Code provides the authorization for conducting the census in Puerto Rico and the Island Areas.  Basic demographic questions are always asked.

Race - Until later in the 1800s, race affiliations recorded on the census were mainly either white or black.  Native Americans could be counted if they did not live on tribal land.  Enumerators based race on observation. If the person being counted for the census was not home when the enumerator arrived, the race recorded might have been based on the community where they lived.  Do not assume that a person cannot be your ancestor because the race listed is wrong. Use other information such as names and ages, tax lists, etc. to determine if it could be your ancestor.

Soundex – A coding system to allow for searching of names that sound alike – for example, Smith vs Smythe or Allen vs Alin. It utilizes the first letter of a surname and assigns numerals for up to the next four consecutive consonants except h, w, and y.  This system can only be applied to the 1880, 1900, 1910, 1920, and some states’ 1930 Censuses.  The Soundex is best used with census microfilm because it points to page numbers. 

Township - An electoral and administrative district of a county.

Learn more:

U.S. Census Bureau- Census Glossary