An Indian Agency for the Potawatomi was established at St. Marys Mission in 1857, and in accordance with the terms of the Treaty of 1861, payment to the Potawatomi was made here on October 29, 1870. These iron gates originally stood at the entrance to St. Mary's College. In 1969, through the cooperation of the City of St. Marys and the St. Marys Historical Society, the site was designated as the Potawatomi Pay Station Museum, and it is listed on the National Register of Historic Sites.