Named for William McHenry, a pioneer of White County, soldier of the War of 1812 and the Black Hawk War, Representative in the first, fourth, fifth and ninth General Assemblies, and Senator in the sixth General Assembly.
The year was 1840 when McHenry County had its first courthouse. Built by William H. Beach to be used as a courthouse and jail, the courthouse was a frame building, located on Riverside Drive in McHenry. It is claimed that the old building is now part of the McHenry House. During the next three years dissatisfaction arose in the county that the courthouse was not centrally located. Over the years, 4 different courthouses would be built.