Martinsville is a city in Washington Township, Morgan County, in the U.S. state of Indiana. The population was 11,828 at the 2010 United States Census. The city is the county seat of Morgan County.
Martinsville was founded in 1822. It is said to be named for John Martin, a county commissioner. A post office has been in operation at Martinsville since 1823.
The Morgan County Courthouse, completed in 1859, features a red brick and Italianate design, and is one of the few pre-Civil War courthouses in Indiana. Architect Isaac Hodgson designed the courthouse, and it was built by Perry Magnus Blankenship. Hodgson designed six Indiana courthouses including Jennings County Courthouse (1859), Morgan County (1857), Henry County Courthouse, Bartholomew County Courthouse (1871), and his largest in Marion County, in Indianapolis.
In 1899, Eugene Shireman, a Martinsville entrepreneur, turned his swamp land into fisheries and started Grassyfork Fisheries. Once dubbed the "Goldfish Capital of the World", today Martinsville has several large fisheries that sell fish to many parts of the world. Shireman's actions changed the landscape of the Martinsville area, and his fisheries can be seen today throughout Shireman subdivision.