Gerrish House Society was formed in 1961 by a group of interested residents of Grand Manan Island, New Brunswick, under the guidance of L. Keith Ingersoll. On 18 June 1974, its name was changed to Grand Manan Museum Inc. Its purpose was to construct a museum for Grand Manan in fulfillment of a desire to preserve local history. There was also a need for a permanent structure to house the Allan Moses Bird Collection (consisting of 300 stuffed birds), which had been given to the children of Grand Manan in 1951. The first structure was a Centennial Project for 1968. Two more major expansions - one in 1979 and one in 1997 - give us the building we have today.

Grand Manan Museum Inc. continues to work closely with the Grand Manan Historical Society. That Society was formed in 1934 by summer resident Buchanan Charles of Massachusetts and interested individuals from Grand Manan and the mainland. This society made the collection of information about Island history its primary aim, while the Museum's mandate is to preserve the artifactual history of the Island.