The Morgan County courthouse was designed by Isaac Hodgson in the Italianate style. It was built from 1857 to 1859 by Perry M. Blankenship of Martinsville at a cost of $32,000. It was almost identical to Hodgson's Jennings County courthouse in Vernon, which was also begun in 1857, but the Martinsville building received an addition in the 1970s; the original section was also remodeled and renovated at that time. The building is of red brick with white stone quoins and has tall windows with round arches, arranged in pairs. It is one of the few remaining pre-Civil War courthouses.
