Mercer county was formed in 1825 from parts of Pike County. It is located in western Illinois on the banks of the Mississippi River just northwest of Galesburg.
The county is named for Hugh Mercer who was a physician and General during the Revolutionary War. It was part of the "Military Tract" ceded to veterans of the War of 1812.
The county seat is Aledo and the county population on July 1, 1999, was 17,644, an increase of 354 over the 1990 census. Aledo's name was derived by drawing letters out of a hat until the first pronounceable word was formed.
One of the four Mark Twain NWRs along the Mississippi is located near Keithsburg.
For information on county government, contact the National Association of Counties Web site.
Additional information is available at these pages:
