| Description: | Greene County, located in central Illinois, covers an area of 543 square miles and had a 2003 population of 14,708, according to estimates by the U.S. Department of Commerce's Bureau of the Census. Using these figures, Greene County was the 46th largest county in Illinois geographically, but 24th smallest in terms of population. Combining these two measures, Greene County had the 15th lowest population density per square mile among Illinois 102 counties. | |