Marshal County, one of the most northern counties of the state, was officially organized on August 25, 1855. Founded by Frank Marshall; A. G. Woodward; John D. Wells; A. G. Barnett; and Joseph Langdon, the county was one of the original 33 counties organized by the Territorial Legislature in 1855. Frank Marshall, upon acceptance of the county as one of the original 33, named the county for himself. Marshall County contains the cities of Summerfield, Blue Rapids, Beattie, Marysville, Axtell, Vermillion, Oketo, Frankfort and Waterville.
Marysville was established as a "home station" on the Pony Express route, 1860-1861, and put the county "on the map." The Central Branch of the Union Pacific Railroad's entrance into the county in 1867 assisted in bringing settlers to the county. Also the founding of the first post office in Kansas Territory on November 11, 1854, which has the longest continual service in the state, was an important moment for the county.
Marshall County has been home to many interesting Kansans such as Kenneth Dam, a native of Marysville, was U. S. Deputy Secretary of State until his resignation in June 1987. Congressman Guy Helvering (1913-1919), who helped write the income tax act, was appointed U. S. Collector of Internal Revenue, by President Franklin Roosevelt. He later was appointed a federal judge.
Marshall County is home to many interesting sites such as the Pony Express Home Station in Marysville, the Koester House Museum in Marysville, the Blue Rapids Public Library, oldest active library in the state, and the Oketo Museum.