Hilda Mason was an American politician and statehood advocate in Washington, D.C. Mason was a member of the D.C. Statehood Green Party and served as an at-large member of the Council of the District of Columbia from 1977 to 1999, becoming, at the time, the longest-serving elected official in the district's history since the beginning of home rule. Mason was one of a few members of the Democratic Socialists of America to be elected to public office before 2017.

All Souls Church, Unitarian is a Unitarian Universalist church located at 1500 Harvard Street NW at the intersection of 16th Street, Washington, D.C., roughly where the Mt. Pleasant, Columbia Heights, and Adams Morgan neighborhoods of the city meet. The design of its current building, completed in 1924, is based on St Martin-in-the-Fields in London, England. It was listed on the National Register of Historic Places in 2020. All Souls, a member of the Unitarian Universalist Association of Congregations, describes its theology as having evolved from a liberal Christian tradition into a "rich pluralism."