A Portland Female Anti-Slavery Society meeting in the First Parish Church in the 1840s resulted in an anti-slavery riot. Stephen S. Foster was visiting speaker. Society members Lydia Neal Dennett and Elizabeth Widgery Thomas (site M18) escorted Foster to safety through a rear window next door to the house of Comfort Hussey Winslow. Winslow held Society meetings in her house as early as 1834. The church, built in 1826, survived the great Portland fire of 1866.
Women in the church have been active in meeting societal needs. Women in the Channing Circle in 1847 raised money in a fair to start the ministry to the poor that eventually became Preble Chapel (site C16). Women in the church formed a branch of the Alliance of Unitarian Women, which still exists, in the late nineteenth century. Three women have served as the church's director, including Rev. Jill Jacob Saxby, installed in 1995; Rev. Frances Buckmaster, and the current director, Rev. Christina Sillari, who was installed in 2010. The church regularly invites women activists in the local community to give lay sermons.