McHenry County Background
McHenry was formed in 1836 from the existing Cook and LaSalle counties. McHenry county bears the name of an Indian fighter named Major William McHenry. He died in Vandalia in 1835. The county originally extended all the way East to Lake Michigan but was reformed to create Lake county. The county seat is in Woodstock. McHenry county is composed of the following townships; Alden, Algonquin, Burton, Chemung, Coral, Dorr, Dunham, Grafton, Greenwood, Hartland, Hebron, Marengo, McHenry, Nunda, Richmond, Riley, and Seneca.
McHenry county is located Northwest of Chicago in the state of Illinois. It borders the ILGenWeb and WIGenWeb counties of: Lake, Cook, Kane, Boone, Walworth (Wisconsin), Kenosha (Wisconsin)