The first seat of government in Clinton County was located in Camache in about 1840. Instead of building a courthouse, officials operated out of hotels and houses. A year later, a wooden building in the town of Vanderburg was donated to accommodate the court. After the size of county government increased, the Exchange Hotel was used for additional space. Eventually the name of the town changed to Dewitt and a second courthouse was constructed in 1854. This building was 40 by 50 feet and cost $6,000.
Political pressure from Clinton resulted in moving the county seat to Clinton in 1869. Clinton county immediately built a new courthouse in Clinton, which measured 44 by 52 feet.
A second courthouse was completed in 1897 for a cost of $168,000. The grand structure was designed by M.S. Mansfield, whose plan was selected from 8 other entries in a contest. It was built of red sandstone and granite. There is a large copper tower in the center which accents the Romanesque style of architecture. This courthouse still proudly serves the people of Clinton.