Frothingham, Octavius Brooks (frŏħˈĭnghəm) [key], 1822–95, American clergyman and writer, b. Boston. While a Unitarian minister in Salem (1847–55) he came under the influence of Theodore Parker. In 1859 he organized the Third Unitarian Church of New York City and soon achieved wide renown. In 1865 his followers, wishing to increase the sphere of his influence, organized the Independent Liberal Church, which was made up of people from all faiths. Frothingham was president of the Free Religious Association in Boston from 1867 until his health broke down in 1878. In addition to writing sermons and such religious books as The Religion of Humanity (1872), he was the author of Transcendentalism in New England (1876), Boston Unitarianism, 1820–1850 (1890), and biographies of his friends—Theodore Parker (1874), Gerrit Smith (1877), and George Ripley (1882).
See his Recollections and Impressions, 1822–1890 (1891).