JHM originated in 1924 from a bequest of 15,000 items by David and John Johnson to the city of Coshocton. They wanted the city to establish a museum as a memorial to their Johnson and Humrickhouse ancestors. These native-born bachelor brothers collected American Indian, European and Asian objects while traveling worldwide and residing in Washington State. On January 6, 1931, a train left Tacoma for Coshocton laden with their bequest filling 109 boxes, 20 crates, 30 barrels, and 2 bales. The collection was given over to the Coshocton County Library Board of Trustees to oversee the collections and a museum. A defunct school building served as its site and it opened its doors in May of 1931. Additional contributions followed, including Ohio historical items and prehistoric Ohio tools and points. In 1979 the museum relocated to a new building in Roscoe Village.