Note: For a more recent overview of the Census Bureau’s history of asking about religion, read this April 2023 article.

The U.S. Census Bureau has not asked questions about religion since the 1950s, but the federal government did gather some information about religion for about a century before that. Starting in 1850, census takers began asking a few questions about religious organizations as part of the decennial census that collected demographic and social statistics from the general population as well as economic data from business establishments. Federal marshals and assistant marshals, who acted as census takers until after the Civil War, collected information from members of the clergy and other religious leaders on the number of houses of worship in the U.S. and their respective denominations, seating capacities and property values. Although the census takers did not interview individual worshipers or ask about the religious affiliations of the general population, they did ask members of the clergy to identify their denomination – such as Methodist, Roman Catholic or Old School Presbyterian. The 1850 census found that there were 18 principal denominations in the U.S.

The same basic questions on religious institutions were included in the 1860 and 1870 censuses. In 1880, census takers started collecting more in-depth information from religious leaders on topics ranging from average worship attendance to church income, expenditures and debt. The scope of inquiry about religion was expanded again in 1890, when census takers gathered information about the number of ministers in each denomination. Classifications for the denominations also were more detailed. The reported number of denominations in the 1890 census totaled 145, most grouped into 18 families.

There were no other significant changes in data collection on religious bodies until 1902, when the U.S. Census Bureau was established as a permanent government agency and census officials decided to separate some data collection from the regular decennial census. This led to the statutory creation of the Census of Religious Bodies, which began in 1906 as a stand-alone census to be taken every 10 years.

The first Census of Religious Bodies, which was conducted through questionnaires mailed to religious leaders, asked many of the same questions as the 1890 census did, plus added a few new questions. It included, for example, questions on the year the congregations were established; amount of congregational debt; language in which services were conducted; number of ministers and their salaries; number of congregation-operated schools, teachers, scholars and officers; and demographic characteristics of congregation members, such as gender. As in the past, census collectors relied on denominational officers to supply the information.

“As its name implies, this is a census of the religious organizations in the United States rather than of individuals classified according to their religious affiliation,” the Census Bureau explained in its report on the 1906 Census of Religious Bodies. The 1906 Census of Religious Bodies was the most thorough compilation of religious organizations to date. It reported a total of 186 denominations, most grouped into 27 families. One reason for the increased number of denominations since 1890 was the influx of immigrants to America.

The Census of Religious Bodies was conducted every 10 years until 1946. The 1936 Census of Religious Bodies was the last one published, however, because the U.S. Congress failed to appropriate money either to tabulate or to publish the information collected in the 1946 census. By 1956, Congress had discontinued the funding for this census altogether.

The unpublished results of the Census of Religious Bodies in 1946 and its ultimate demise in 1956 stemmed in part from a growing public debate over the propriety, merit and feasibility of the Census Bureau asking questions about religion. During the 1950s, religious groups, civil liberty groups, social scientists and even the Census Bureau’s own staff were sharply divided over the issue. Those opposed to including questions on religion had concerns about the protection of religious liberty and privacy rights, and whether the government was overstepping the constitutional boundaries separating church and state. Those who favored including questions on religion felt there was some value in learning about people’s religious affiliations in states and localities, and that it could help religious leaders in planning for future building programs and activities.

There was a concerted campaign by researchers, some leaders in the Catholic Church and Census Bureau Director Robert W. Burgess, an economist and statistician, to include a “What is your religion?” question in the 1960 Census of Population. But Burgess eventually decided against it after receiving vocal opposition from some religious and civil liberties groups. “[A]t this time a considerable number of persons would be reluctant to answer such a question in the [c]ensus where a reply is mandatory,” Burgess stated in 1957 when he agreed not to include a question on religion. “Under the circumstances, it was not believed that the value of the statistics based on this question would be great enough to justify overriding such an attitude. Cost factors were also a consideration.” Burgess said the decision did not preclude the inclusion of a question on religion in a future census.

Neither Burgess’ decision nor the discontinuation of the Census of Religious Bodies signaled the complete end to data collection on religion by the Census Bureau, however. In 1957, the Census Bureau included a few questions on religious affiliation in its Current Population Survey, the nation’s primary source of information on America’s labor force. This marked the first time that individuals rather than religious leaders were asked about their religious affiliation in a census. Individuals’ religious affiliations were classified into major faith traditions, other religions, no religion and religion not reported. Because respondents were classified by age, race, gender and education, the Census Bureau was able to produce a set of tables showing intermarriage, fertility, employment, income, urban residence and education among various religious faiths. Several reports from this data were originally planned for publication, but the Census Bureau ultimately released only a short pamphlet that included some of the information from the cross-referenced tables.

In the 1960s and 1970s, the Census Bureau again considered a number of requests from individuals and organizations to include a question on religion in the regular decennial census. The Census Bureau, however, decided the question would not be included in the 1970 census because it felt the question would “infringe upon the traditional separation of church and state.”

By the mid-1970s, the issue arose again and was discussed at public meetings held in cities around the nation about the Census Bureau’s plans. Proponents of including a question on religion stressed the importance of religion in American life and noted that a question on religion was included in the censuses of other countries, such as Canada and Australia.

However, the Census Bureau director at that time, Vincent P. Barabba, announced in April 1976 that a question on religion would not be included. “The decision not to add this question is based essentially on the fact that asking such a question in the decennial census, in which replies are mandatory, would appear to infringe upon the traditional separation of church and [s]tate,” according to a 1976 press release drafted by the Census Bureau. “Regardless of whether this perception is legally sound, controversy on this very sensitive issue could affect public cooperation in the census and thus jeopardize the success of the census.”

Barabba’s decision was reinforced in October 1976 when Congress enacted a law containing a number of amendments to the basic census law, including a prohibition against any mandatory question concerning a person’s “religious beliefs or to membership in a religious body.”

Since then, the Census Bureau has been allowed to ask questions about religious practices only on a voluntary basis in some population and household surveys, but it has not opted to do so. The only information the Census Bureau now collects and publishes about religion and religious bodies is county-by-county economic data on places of worship and other establishments operated by religious organizations. This information is included in an annual series on County Business Patterns that reports on most of the nation’s economic activity. The Census Bureau also publishes information about religious bodies and religious affiliation in the Statistical Abstract of the United States, but this information is derived and reprinted from nongovernmental survey organizations, such as the Yearbook of American and Canadian Churches and The American Religious Identification Survey, which are not related to the Census Bureau.

This essay was originally published in 2008 as an appendix to the U.S. Religious Landscape Survey and was written by Anne Farris Rosen for the Pew Research Center’s Forum on Religion & Public Life.

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