About Western Illinois
Rock Island County is a county located in the U.S. state of Illinois, bounded on the west by the Mississippi River. According to the 2010 census, it had a population of 147,546. Its county seat is Rock Island; its largest city is neighboring Moline. Rock Island County is one of the four counties that make up the Davenport-Moline-Rock Island, IA-IL Metropolitan Statistical Area. Rock Island County was formed in 1831 out of Jo Daviess County. It was named for Rock Island, an island in the Mississippi River now known as Arsenal Island.
Content courtesy of wikipedia.org