First Parish of Norwell traces its origins to the First Parish of Scituate, which was established in 1634. In 1641, the congregation split during the ministry of Rev. Charles Chauncy, who had fled to North America to escape persecution by English authorities. The church's congregants disagreed as to whether baptism should consist of full submersion or mere "sprinkling". More liberal members, who considered full submersion to be unnecessary, left to form a Second Church of Scituate in February of 1642, under the leadership of William Vassall. It is likely that the first meetings of the separatist congregation were held in Vassall's own home at Belle House Neck.
Mr. Thomas King was chosen as the first Elder of the church, but meanwhile the new congregation struggled to find a minister who would be accepting of their liberal standards. Eventually they settled on Rev. William Wetherell of Duxbury, who was ordained in September of 1645. His ordination was delayed by the continuing opposition of Rev. Chauncey and the First Parish of Scituate, as well as their regional allies, but was eventually confirmed by an ecclesiastical council. Under his pastorate the congregation grew significantly, necessitating the erection of a larger meeting house in 1680, located either in or near the current old cemetery on Main Street, Norwell. This was followed in 1707 with a larger building constructed on Herring Brook, and later by a fourth building on the same site in 1769.
Noted successors of Rev. Wetherell were the Reverend Nathaniel Eells (1704-1750), Rev. David Barnes (1754-1811), Rev. Samuel Deane (1810-1834), and Rev. Samuel Joseph May (1836-1842). Reverends Eells and Barnes in particular were liberal ministers who probably paved the way for the congregation's eventual embrace of Unitarianism. This affiliation was made official in 1820 and was an uncharacteristically unanimous decision, with only one member requesting dismissal as a result.
In 1830 the fifth and current meeting house was built. It was designed by William Sparrell, a native of Norwell. The 1830s also saw an increase in the visibility of the abolitionist movement, with William Lloyd Garrison and other Bostonians campaigning for the emancipation of slaves. Among Garrison's supporters was Reverend Samuel J. May, minister of Norwell from 1836-1842. Rev. May, the uncle of author Louisa May Alcott, was a fervent supporter of women’s rights, the anti-war movement, and total abstinence from alcohol. He organized the first church school in the parish, and created a local chapter of the "Cold Water Army", a group which promoted abstention from all intoxicants with banners and parades. Rev. May spoke publicly against the segregation of black and poor parishioners who were consigned to the balcony of the church. This created widespread dissent in the congregation and ultimately led to his resignation in the summer of 1842.
The area encompassing the current church and town was incorporated as South Scituate in 1849, and changed again to Norwell in 1888. First Parish of Norwell, a Unitarian Universalist affiliated church, continues to serve the community today.