McHenry County, Illinois
Founding: 1837 (declared in 1836) Parent county: Cook Namesake: William McHenry, Illinois politician Seat: McHenry (1836–1843); Woodstock (1843–) Land area: 603 square miles Population (2020): 310,229 Population (historic): 2,578 (1840); 22,089 (1860); 24,908 (1880); 29,759 (1900); 35,079 (1930) Periods of population growth: pre-1840–2020 Subdivisions: Five cities; two CDPs; 17 townships Pre-1940 residences (estimated): 9,246 (7.8%) Pre-1940 housing survival rate: 82.7% Pre-1860 housing survival rate (1940): 12.5% Farm housing in disrepair (1950): 4.5% Nonfarm housing in disrepair (1950): 2% Average farmhouse value (1930): $2,483 Average outbuilding value (1930): $3,560 Average farmhouse size (1940): 7.6 rooms Number of farms (1920): 2,874 Average farm size (1920): 92 acres Sources of settlement: New York, Germany, Ireland, Wisconsin, and Vermo...