Wrentz County was created in 1825 by explorers from the Colony of Vegetano. In 1843, part of the county became part of LeDoux County. Wrentz County's first county seat was at DeCaffee. DeCaffee served as the county seat until 1847, when it was moved to Haagsville. It was moved to Dellstown in 1859. In 1964, the residents voted to have two county seats. That year, Dellstown and Haagsville became the county's two seats. These cities remain the county seats.