Being one of the oldest surviving county historical society in Pennsylvania, the Cumberland County Historical Society (CCHS) has cause for celebration during its 125th anniversary year. Founded in 1874 as the Hamilton Library Association, the Society's first century is recalled by Milton E. Flower in the publication "The First One Hundred Years". It concludes with the Society undertaking a 4,128 square foot addition that opened September 24, 1975 in time for America's Bicentennial. Almost like a matching bookend, CCHS burned the mortgage for its 1998 addition in 1999 in time to celebrate Cumberland County's 250th anniversary and the start of the new millennium in the year 2000. The two expansions bracket twenty-five years of the extraordinary growth and transition from a small historical society to a professional organization.
As the accompanying chart reflects, CCHS growth in the last twenty-five years has been incredible, but the impetus for this growth started long before 1975. It can be traced to the 1960s when Robert G. Crist, Milton E. Flower, Pierson K. Miller, Roger K. Todd, and Jonas S. Warrell crystallized their desire to realize the Society's mission of preserving and sharing Cumberland County history and heritage with others. Aggressively lead and inspired by Dr. Flower, their combined advocacy of CCHS and dedication to pursue the goals of increasing collections, offering more programs, and initiating substantive historical projects resulted time and again in the need for additional space. First came the 1964 expansion plans to the original 1881 building that added what are now the central office, Rupley Room, and kitchen. Taking advantage of an opportunity provided by the weakened south wall caused by the 1972 fire next door, the 1975 addition followed with a new entrance foyer, the multi-purpose Todd Hall, and the expansion of the second floor museum galleries. Within twenty years, Ann Kramer Hoffer would again describe the need for more space that resulted in the latest and largest of additions in 1998. "We are literally at a loss for space. Researchers are lined up at computers beside book stacks. Volunteers vie for seats with library users. School children cram through the reading room to the museum upstairs. Manuscripts and photographs are crowded into small vault space storage has become a critical problem overflowing to a rented off-sire location. A program/exhibit hall (Todd Hall) on the first floor can no longer serve dual purposes."