Greene County is a county located in the U.S. state of Ohio. As of the 2010 census, the population was 161,573. Its county seat is Xenia. The county was established on March 24, 1803 and named for General Nathanael Greene, an officer in the Revolutionary War.Greene County is part of the Dayton, OH Metropolitan Statistical Area.GeographyAccording to the U.S. Census Bureau, the county has a total area of, of which is land and (0.6%) is water.Adjacent countiesClark County (north)Madison County (northeast)Fayette County (east)Clinton County (south)Warren County (southwest)Montgomery County (west)National protected area Dayton Aviation Heritage National Historical Park (part)
