Growing Out of a Congregational Quarrel

The American Unitarian Association was formally organized in 1825, but it represented the institutional outcome of a much longer and more gradual theological shift that had been building within New England Congregationalism since the late eighteenth century, as a growing number of Congregationalist ministers and congregations moved away from Trinitarian doctrine and toward a Unitarian understanding of God as a single undivided person rather than three persons in one being. Ministers such as William Ellery Channing became the movement's most influential public voices, arguing for a rational, non-creedal Christianity that emphasized moral character and the free use of reason in interpreting scripture over strict doctrinal conformity to inherited confessions of faith. Rather than beginning as a wholly new denomination founded from outside, American Unitarianism grew from within existing Congregationalist churches, several of New England's oldest congregations, including some tracing back to the earliest Puritan settlements, gradually adopting Unitarian views over the early nineteenth century, a pattern of quiet internal transformation rather than sudden schism that shaped how the young denomination understood its own relationship to the wider American Protestant tradition it had grown out of.