The White River Valley Museum was first conceived by a group of towns people who in the 1950's gathered over lunch and shared stories of regional history. The group eventually formed a non-profit corporation, the White River Valley Historical Society, and started a small museum in the town of Thomas, between Kent and Auburn. In the late 1960's the society had to move from the borrowed Thomas facility, so they raised funds and built a museum building on city of Auburn property, in Les Gove Park. In 1989, as the group was aging and had lost several members, they began to seek out city support to keep the museum alive and well. Much to its credit, the City of Auburn agreed to partner with the Historical Society, and in 1990 a Museum Services Agreement was developed that secured the Museum's future as an official city entity. Today a 17-member board manages the Museum as a partnership between the White River Valley Historical Society and the City of Auburn.
The mission of the Museum is to preserve and share the history of the South King County area, known by pioneers as the White River Valley (Auburn, Kent, Algona and Pacific.) This mission is carried out primarily through the operation of the Museum and the 67-acre, landmark Mary Olson Farm, a late 19th century farmstead east of the Green River.