Plymouth is a city in Sheboygan County, Wisconsin, along the Mullet River. It is included in the Sheboygan, Wisconsin Metropolitan Statistical Area. The city is located in the Town of Plymouth, but is politically independent. Plymouth is known as "Hub City" for its former role as a center of wooden wheelwrighting. The population was 8,445 at the 2010 census. Mayor Don Pohlman was last re-elected in April 2018.
Plymouth was surveyed in 1835 by United States engineers, one of whom was named Mullet, and the Mullet river was subsequently named after him. The first land sold to a private party was sold to an Englishman named John Law who had emigrated from London. It was sold to Law on August 13, 1836. The next sale was to another Englishman, also from London, named Thomas Margrave.