The Longyear Museum documents the life of Mary Baker Eddy, who worked hard to establish Christian Science in Lynn, Boston, Chestnut Hill, Massachusetts, and Concord. The Museum also follows the lives of the Christian Scientists who supported and assisted Mrs. Eddy in fulfilling this purpose.

The Museum was founded by Mary Beecher Longyear, a philanthropist, in preserve the early history of the Christian Science religion through the preservation of documentary evidences and facts about Mary Baker Eddy.

The Longyear Museum officially opened in Brookline, the site of the former home of Mrs. Longyear, in 1937. Today, it is located in Chestnut Hill where visitors can take a look at its new exhibit halls, which opened for public viewing in 2001. The Museum features a collection that includes paintings, documents, furniture, photographs, and artifacts that are related to the life and works of Mrs. Eddy. There are also four houses on the site that also served as a residence for Mrs. Eddy. As time passed, 4 houses were added to the site in order to provide a bigger venue for sharing the legacy of the inspirational woman.