[2] The Hancock House was built by philanthropist Horace A. Moses for the New York State Historical Association as a repository for "American Traditions in History and the Fine Arts;" the Association used it as its "Headquarters House" until after World War II.

As his wealth grew, he made a series of substantial donations to many Ticonderoga projects, among which were the Valley View Cemetery Chapel, the Liberty Monument, the Moses-Ludington Hospital, the Community Building, and the Hancock House; with the last of these, he accomplished an early lifetime ambition—to establish a museum with a library that would make Ticonderoga a focal point for public interest in the region's history.

The Ticonderoga Historical Society today manages the building as a regional museum and reference library.

The library houses a large collection of regional material on civic, social and economic matters and has one of the largest collections of genealogical resource materials in the region.

Ticonderoga history is emphasized in the collection of photographs, manuscripts, artifacts, and books kept in the museum.