- Population: 6,445 (Change since 1990: -6.7%)
- Created: September 14, 1812
- County seat: Shawneetown
- Largest town: Shawneetown (Pop. 1,410)
- Name origin: Albert Gallatin
- Bowlesville (Unincorporated)
- Located southwest of Shawneetown
- Latitude & Longitude: 37°40'27" N, 88°12'45" W
- Survey: T. 10 S., R. 9 E.
- Elevation: 425
- Precinct: Bowlesville
- USGS Quad: Shawneetown
- Cottonwood (Unincorporated)
- Located east of Omaha at the intersection of Noel Road and Mills Road
- Latitude & Longitude: 37°53'21" N, 88°12'47" W
- Survey: T. 7 S., R. 9 E.
- Elevation: 410
- Precinct: Asbury
- USGS Quad: New Haven
- Elba (Unincorporated)
- Located northwest of Ridgway at the intersection of Elba Road and Zion Cemetery Road
- Latitude & Longitude: 37°49'35" N, 88°19'35" W
- Survey: T. 8 S., R. 8 E.
- Elevation: 360
- Precinct: North Fork
- USGS Quad: Ridgway
- Equality (Village)
- Population: 721 (Change since 1990: -3.6%)
- Located near intersection IL 13 and IL 142 southeast of Eldorado
- Latitude & Longitude: 37°44'02" N, 88°20'36" W
- Gibsonia (Unincorporated)
- Located near the IL 1 bridge over Eagle Creek northwest of Saline Mines
- Latitude & Longitude: 37°38'49" N, 88°15'45" W
- Survey: T. 10 S., R. 9 E., Sec. 18
- Elevation: 365
- Precinct: Bowlesville
- USGS Quad: Equality
- Inman (Unincorporated)
- Located on the Shawneetown New Haven Road near the intersection
with Moye Road
- Latitude & Longitude: 37°50'16" N, 88°10'23" W
- Survey: T. 8 S., R. 9 E.
- Elevation: 376
- Precinct: Ridgway
- USGS Quad: New Haven SW
- Junction (Village)
- Population: 139 (Change since 1990: -30.8%)
- Located along IL 13 west of Shawneetown
- Latitude & Longitude: 37°43'24" N, 88°14'12" W
- Kedron (Unincorporated)
- Located south of Equality along Kedron Road
- Latitude & Longitude: 37°39'56" N, 88°20'29" W
- Survey: T. 10 S., R. 8 E., Sec. 8
- Elevation: 383
- Precinct: Eagle Creek
- USGS Quad: Equality
- Lawler (Unincorporated)
- Located between Equality and Junction on IL 1
- Latitude & Longitude: 37°43'41" N, 88°17'09" W
- Survey: T. 9 S., R. 8 E., Sec. 23
- Elevation: 372
- Precinct: Equality
- USGS Quad: Equality
- Leamington (Unincorporated)
- Located west of Gibsonia along Leamington Road
- Latitude & Longitude: 37°38'22" N, 88°18'25" W
- Survey: T. 10 S., R. 8 E., Sec. 22
- Elevation: 390
- Precinct: Eagle Creek
- USGS Quad: Equality
- New Haven (Village)
- Population: 477 (Change since 1990: +3.9%)
- Located along IL 141 at the northeast corner of the county
- Latitude & Longitude: 37°54'31" N, 88°07'45" W
- New Market (Unincorporated)
- Latitude & Longitude: 37°47'30" N, 88°14'18" W
- Elevation: 392
- Precinct: Ridgway
- USGS Quad: New Haven SW
- Map: 1883 Tenney
- Old Shawneetown (Village)
- Population: 278 (Change since 1990: -21.9%)
- Located on IL 13 at the bridge over the Ohio River
- Latitude & Longitude: 37°41'49" N, 88°08'12" W
- Omaha (Village)
- Population: 263 (Change since 1990: -3.7%)
- Located along IL 1 northwest of Ridgway
- Latitude & Longitude: 37°53'25" N, 88°18'11" W
- Post office: Feb. 17, 1871 - Now
- Ridgway (Village)
- Population: 928 (Change since 1990: -15.9%)
- Located northwest of Shawneetown just off IL 1
- Latitude & Longitude: 37°47'57" N, 88°15'40" W
- Saline Mines (Unincorporated)
- Located south of Shawneetown near Saline River
- Latitude & Longitude: 37°37'17" N, 88°11'02" W
- Survey: T. 10 S., R. 9 E., Sec. 26
- Precinct: Bowlesville
- USGS Quad: Saline Mines
- Shawneetown (City)
- Population: 1,410 (Change since 1990: -10.5%)
- Located along IL 13 northwest of Old Shawneetown and east of Equality
- Latitude & Longitude: 37°42'47" N, 88°11'12" W
- Wells (Unincorporated)
Name origin
Named for Albert Gallatin, U.S. Secretary
of the Treasury, among other things
| Year | Population | Percent change |
|---|
| 1820 | 3,155 | -- |
| 1830 | 7,405 | +134.7% |
| 1840 | 10,760 | +45.3% |
| 1850 | 5,448 | -49.4% |
| 1860 | 8,046 | +47.7% |
| 1870 | 11,134 | +38.4% |
| 1880 | 12,861 | +15.5% |
| 1890 | 14,935 | +16.1% |
| 1900 | 15,836 | +6.0% |
| 1910 | 14,628 | -7.6% |
| 1920 | 12,856 | -12.1% |
| 1930 | 10,091 | -21.5% |
| 1940 | 11,414 | +13.1% |
| 1950 | 9,818 | -14.0% |
| 1960 | 7,638 | -22.2% |
| 1970 | 7,418 | -2.9% |
| 1980 | 7,590 | +2.3% |
| 1990 | 6,909 | -9.0% |
| 2000 | 6,445 | -6.7% |