The Presbyterian Historical Society (PHS) is the oldest continuous denominational historical society in the United States. Its mission is to collect, preserve and share the history of the American Presbyterian and Reformed tradition with the church and broader community. It is a department of the Office of the General Assembly of the Presbyterian Church (U.S.A.).

The Presbyterian Church (USA), abbreviated PCUSA, is a mainline Protestant denomination in the United States. It is the largest Presbyterian denomination in the country, known for its progressive stance on doctrine and its ordaining of women and members of the LGBT community as elders and ministers. The Presbyterian Church (USA) was established with the 1983 merger of the Presbyterian Church in the United States, whose churches were located in the Southern and border states, with the United Presbyterian Church in the United States of America, whose congregations could be found in every state.