Hessen Cassel is an unincorporated community in Marion Township, Allen County, in the U.S. state of Indiana. History Hessen Cassel was platted in 1863. Hessen Cassel was originally built up chiefly by Germans, and was named for the Landgraviate of Hesse-Kassel in Germany. Geography Hessen Cassel is located at . References Unincorporated communities in Allen County, Indiana Unincorporated communities in Indiana Fort Wayne, IN Metropolitan Statistical Area