Rushville is a city in Rushville Township, Rush County, in the U.S. state of Indiana. The population was 6,341 at the 2010 census. The city is the county seat of Rush County. It, like the county, was name…Rushville is a city in Rushville Township, Rush County, in the U.S. state of Indiana. The population was 6,341 at the 2010 census. The city is the county seat of Rush County. It, like the county, was named in honor of Dr. Benjamin Rush, who signed the Declaration of Independence.