The Moravian University and Moravian Theological Seminary Archives was established as a distinct department of Reeves Library in 1987, under the direction of Professor Emeritus Daniel Gilbert. Assembled from a variety of sources, both inside and outside the Library, the materials housed in the Archives include documents relating to Nazareth Hall Academy, the Moravian Seminary for Young Ladies, and the Moravian College for Women. These are mostly twentieth century materials, though some date from the nineteenth century, a very few from the eighteenth, and a growing number from the twenty-first.

The Archives housed in Reeves Library is separate from, though in some ways closely related to, the archives of the Moravian Church.