Our congregation was formed in 1651 by Pilgrims who had left Duxbury, Massachusetts. The church was Congregationalist, and our first long-time minister was James Keith, who preached his inaugural sermon at Pulpit Rock, Memorial Park, West Bridgewater, Massachusetts, in 1652. He served until 1719.

The Reverend James Keith Parsonage, sometimes called the Keith House, is a 17th-century parsonage owned and maintained by the Old Bridgewater Historical Society (OBHS) in West Bridgewater. Located at 199 River Street, it is thought to be the oldest remaining parsonage in the United States.

The next minister, Daniel Perkins, served until 1782.

In the 1820s, there was considerable theological dispute within Congregationalist circles, with much debate surrounding Calvin's doctrines.

Our church voted to identify as Unitarian, and several Trinitarians departed to join other churches. But the separation proved to be temporary, as something extraordinary happened in 1954: the merger of a Unitarian and a Congregational church.

We changed our name to The First Congregational-Unitarian Church, subsequently changed to The First Church. We maintain links to both the United Church of Christ (UCC) and the Unitarian Universalist Association (UUA).