Chimacum is an unincorporated community in Jefferson County, Washington, United States, located in the center of the primary agricultural area of the eastern Olympic Peninsula. It was named after the Chimakum group of Indigenous Americans that lived there until the late 19th century but are now extinct as a distinct cultural group after losing successive conflicts with neighboring tribes.The Chimacum Valley remains and maintains an identity as a progressive agricultural area with many small locally owned farmsteads, a full-service farmstand grocer carrying locally produced goods, and a community farmers' market held from June to October each Sunday from 10 AM to 2 PM. The area is also served by a local branch of The National Grange of the Order of Patrons of Husbandry who celebrated their 90th anniversary in 2008.