Congregation Adath Israel was established in 1919 by a small group of Jewish farmers in Newtown, Connecticut. The synagogue expanded its building in 1957 and converted from the Orthodox movement to the Conservative movement in the 1970s. In 2007, they relocated to a larger building within Newtown. The collection primarily consists of administrative and financial records, along with newspaper clippings, photographs, and miscellaneous documents.

The Vilna Shul is the last immigrant-era synagogue building in Boston and currently operates as a cultural center. This collection contains correspondence, meeting minutes, reports, proposals, photographs, notes, publications, financial records, legal documents, architectural plans, and audiovisual materials relating to the activities, internal proceedings, finances, early history, building renovations, and legal disputes of the Vilna Shul.