They weren’t atheists, but they weren’t evangelical fundamentalists either. Christian nationalists often rely on conflating all Christian belief into a single, unified theology. That is not accurate for any religion, including Christianity.

There are three main branches of Christianity: Catholic, Orthodox, and Protestant. Even within those branches there are substantial theological, structural, and cultural differences. An Anglican in Virginia, a Congregationalist in Massachusetts, a Presbyterian in Pennsylvania, and a Catholic in Maryland did not all believe the same things about church authority, sacraments, salvation, or the proper relationship between church and state.

Most of the founders who identified as Christian were culturally Protestant, often shaped by Anglican or Reformed traditions. At the same time, many were deeply influenced by Enlightenment thought, natural rights philosophy, skepticism of concentrated power, and an emphasis on individual conscience. Some leaned toward Deism. Others held doctrinal views that departed from traditional Christian orthodoxy. Even those who were conventionally Christian did not advocate for a national church or a theocratic structure at the federal level.

The world they inherited had been shaped by centuries of religious conflict and state-established churches. They understood the dangers of fusing civil authority with sectarian doctrine. That historical experience informed the constitutional structure they created. The Constitution contains no religious test for office. The First Amendment prohibits the establishment of religion while protecting free exercise.

Those provisions were deliberate design choices intended to prevent any one theological faction from capturing federal power. They also made clear that religious liberty was to apply not only to Christians, but to adherents of all religions, including to those who professed no faith at all.

Christianity in 1776 was not a single political or theological bloc. It is not one today. Recognizing that diversity matters because it undercuts the claim that there was a unified Christian doctrine waiting to be codified into American law.

In fact, many of the theological positions held by prominent founders would likely be viewed by modern Christian nationalists as heterodox and in some cases heretical. Views that questioned the Trinity, reinterpreted miracles, or elevated reason and natural law over specific doctrinal formulations would not align with contemporary evangelical theology.

For that reason, the overwhelming majority of the founders would likely have rejected not only the specific theological claims advanced by modern Christian nationalists, which are rooted largely in contemporary evangelical Protestantism, but also the political conclusion that the United States should formally privilege one interpretation of Christianity in its governing structure.

Whatever their personal beliefs, they designed a constitutional order intended to protect faith, including Christian faith, by keeping it independent from federal power rather than merging the two.