Gazetteer/Almanac
Headnote
JEFFERSON COUNTY, situated toward the south part of Illinois. Area, 576 square miles. Face of the country level. Seat of justice, Mount Vernon. Pop. in 1820, 691; in 1830, 2,555; in 1840, 5,762; in 1850, 8,109. (Fanning's, 1853)