In 1821, the congregation of All Souls Unitarian Church first organized as the First Unitarian Church. The original edifice stood at Sixth and D Streets NW; however, in 1877, the congregation erected a new church at Fourteenth and L Streets, changing the name to All Souls Unitarian Church.
Encroaching businesses and houses compelled a second move to its present site in 1924 at Sixteenth and Harvard Streets NW, where the magnificent new church, designed by Coolidge, Shepley & Bulfinch, stands. The design of the edifice is based on James Gibbs’ St Martin-in-the-Fields on Trafalgar Square in London. The exterior walls are of mellow red brick and white stone trim, adorned with a Corinthian portico and pilasters, and an ornate steeple. The parish house adjoins the church proper in the rear.
Notable members of All Souls Unitarian include figures such as Millard Fillmore, John C. Calhoun, Daniel Webster, Charles Sumner, and the historian George Bancroft. William Howard Taft, another member of the church, had his funeral services there.
DC Inventory: November 8, 1964 (Joint Committee on Landmarks)
National Register: December 7, 2020