Staff Photo by Robin Rudd / Cherry blossoms, in full bloom, frame the steeple of the former First Methodist Church near the corner of Georgia Ave. and McCallie Ave. The steeple is all that remains of the church building that dates from 1881 and ceased services in 1967 when it merged with Centenary Church to become First Centenary United Methodist.

While the religious diversity of the United States continues to grow, the Southeast remains the most religiously homogeneous and majority white Christian region of the country.

The county-level data released this past week for nearly 460,000 Americans from the Public Religion Research Institute's "2020 Census of American Religion" showed Tennessee, Georgia, Alabama and Mississippi as outliers in the increasingly religiously diverse nation.

Eight of the 10 least religiously diverse counties in the United States are in Mississippi, according to the study, which measured diversity by the percentage of each major U.S. religion in the county. Urban areas, including in New York and near Washington, D.C., are among the most religiously diverse.

The study also found that, nationwide, the percentage of religiously unaffiliated Americans has stabilized after increasing for eight straight years and the falling percentage of white Christians has stabilized as well.

Notably, between 2018 and 2020, the percentage of white mainline Protestants, or those who did not identify as evangelical or a "born-again Christian," surpassed the percentage of white Evangelical Christians. In 2020, 16.4% of Americans identified as white mainline Protestants and 14.5% of Americans identified as white evangelical.

Robert Jones, the CEO of the institute, told Religion News Service on Thursday that "over the last two years in particular, white mainline Protestants seem to have absorbed at least some folks leaving white evangelical and other churches who may have otherwise landed in the religiously unaffiliated camp."

Jones cautioned there is not enough granular data to say whether evidence is definitive. The institute's analysis was based on 53,474 bilingual phone interviews in 2019 and a data set of 453,822 interviews since 2013.

(READ MORE: Is Chattanooga losing its edge as the most 'churched' and 'Bible-minded' city in the country?)

Hamilton County is less religiously diverse than the four other major metropolitan counties of Tennessee. According to the study, 56% of Hamilton County residents identify as white Christians and 33% of residents identify as white evangelicals, both of which outpace the national averages for those categories — 44% and 14%, respectively.

Of all the other religious categories — which include Hispanic Protestants, Hispanic Catholics, white Catholics, Latter-day Saints, Jewish, Muslim, Hindu, Buddhist and religiously unaffiliated — the only other categories in which Hamilton County outperforms national averages is with white mainline Protestants and Black Protestants.

Hamilton County has a lower Catholic population than the nation as a whole, according to the report, with 4% white Catholics compared to 12% in the nation as a whole, and with 2% Hispanic Catholics compared to 4% nationwide.

In recent years, Chattanooga has ranked among the "most churchgoing" or "most Bible-minded" cities in the country, according to studies by Barna Group. The city ranked first for churchgoing in 2017 and first for Bible-mindedness in 2014.

The Public Religion Research Institute study found that white evangelicals are among the oldest religious groups in the country, with a median age of 56. For comparison, the median age for Black Protestants was 50, and the median was 42 for Hispanic Catholics.

The majority of both political parties — 83% of Republicans and 69% of Democrats — identified as Christian. However, the study found that Democratic voters were more religiously diverse than their Republican counterparts.

Analysis released last month by the Pew Research Center found former President Donald Trump increased his share of white evangelical voters in the most recent presidential election, carrying 84% of their votes in 2020 compared to 77% in 2016.

Contact Wyatt Massey at or 423-757-6249. Follow him on Twitter @news4mass.