The Catholic–Evangelical divide
A county map of American faith — where Catholics lead, where Evangelicals lead, and what the rest of the country believes instead.
One country, two faiths
In 2020, the US Religion Census counted the adherents of every tradition in every county. Color each county by which of the two largest Christian traditions claims more of its people — Catholic in amber, Evangelical Protestant in teal — and the country settles into a familiar seam.
Evangelical Protestantism holds the interior South, Appalachia, the Ozarks, and the southern Plains. Catholicism holds the Northeast, the industrial Upper Midwest, south Louisiana, and the Hispanic counties of the Southwest. Most of the West reads pale: neither tradition comes close to a majority there.
Evangelicals hold the map
Evangelical Protestants are the larger tradition in 2,053 of the 3,134 counties with data — roughly two in three. The belt runs unbroken from the southern Appalachians across the Deep South and up through the Ozarks into the southern Plains.
It is a map of small and mid-sized counties: dense on the page, but thinner on people than its reach suggests.
Catholics hold the people
Catholics lead in 873 counties — far fewer — but those counties hold 54.1% of the population, against 41.5% in the Evangelical-leaning ones. The Catholic map is a map of cities: the Northeast corridor, the Great Lakes, south Louisiana, and the Rio Grande.
Nationwide, that makes Catholics the larger of the two traditions — 18.6% of Americans in 2020 to Evangelicals' 16.5%. Evangelicals win the map; Catholics win the count.
And the unclaimed country
Across most of the map, neither tradition is close to a majority — because most Americans are claimed by no congregation at all. The 2020 census left 51.5% unaffiliated nationwide.
That share runs highest up the Pacific coast, through the interior West, and across northern New England. Humboldt County, CA sits at 80.8%. Recolored for the unaffiliated, the divide map turns into a map of absence.
Where each map peaks
Four counties mark the corners of the story. Imperial County, CA is the most Catholic county of any size — 75.4% Catholic to 6.1% Evangelical. Etowah County, AL is its mirror, 64.5% Evangelical to 4.9% Catholic.
Humboldt County, CA is the most unchurched, at 80.8%. And Fulton County, GA is the rare even split — 16.4% Catholic, 16.6% Evangelical — the seam itself, drawn through a single county.
Method, briefly
Adherence comes from the 2020 US Religion Census, compiled by the Association of Statisticians of American Religious Bodies. Every county is colored by the difference between its Catholic and Evangelical Protestant adherents, each measured as a share of total population. Traditions are grouped on the RELTRAD framework: “Evangelical Protestant” collects Baptist, Pentecostal, nondenominational, and related bodies into one tradition, the same way the census does.
Adherent counts are reported where congregations are located, which can pull membership toward the county of a large parish or megachurch; the “no religion” share is everyone left unclaimed by any reporting body, not a survey of belief. County leans count every county with data; population shares weight those counts by 2020 population. The figures here are drawn from the same data behind Akashic’s national map explorer and every county page.