Mercersburg theology refers to a specific theological school of thought that emerged in the mid-19th century in the United States. Synonyms for this term may include, but are not limited to, the following: the Mercersburg movement, the Mercersburg school, and the Mercersburg theology tradition. This theological movement was characterized by a focus on the sacramental nature of Christianity, and an emphasis on the unity of the church. It also emphasized the importance of tradition and liturgy in worship. While Mercersburg theology has fewer adherents today, it remains an important part of American religious history and theological thought.