The insurance records of Newark, Delaware, realtor, insurance agent, and notary Samuel Mathewson (S.M.) Donnell provide information about Newark property holders and building structures related to Donnell's job as agent for two insurance companies: Fire Association of Philadelphia and Royal Insurance Company of Liverpool, England.

The Hugh F. Gallagher, Jr., family papers document the lives of a 20th century family from Newark, Delaware, and contain a wide variety of papers, clippings, and printed material related to the history and development of Newark, civic activities, and University of Delaware alumni activities. The bulk of the papers come from Hugh F. Gallagher, Jr., a realtor and one of the first developers of suburban Newark, Delaware.