Randolph County, Illinois

Randolph County is a county in Illinois, United States, on the east bank of the Mississippi River in the region locals call “Little Egypt.” It had a population of 30,163 at the 2020 census and covers 597 square miles (1,550 km2) — 576 square miles of land and 22 square miles of water — centred near 38°03′N 89°49′W.

Chester is the county seat, and its postal code is 62233. The county has three cities (Chester, Red Bud and Sparta), eleven villages and roughly two dozen unincorporated communities. Randolph has no township government — the state classifies it among the 17 Illinois counties that use election precincts instead, so county government, not township boards, runs local administration. The whole county sits in the Central time zone.

Towns & Villages in Randolph County

Forty-plus named places appear on the county map, split between three incorporated cities, eleven incorporated villages, and a long tail of unincorporated crossroads and rural communities (Unincorp.) that never took a municipal charter. Historic Kaskaskia — Illinois’s first state capital — is one of the smallest and oldest, cut off from the rest of the county since an 1881 Mississippi River flood shifted the channel and left it on the Missouri side of the river.

Two names on the county map need a note. Kaskaskia and Old Kaskaskia are two separate entries: the modern village sits on the reshaped river landform west of the main channel, while “Old Kaskaskia” refers to the original townsite the 1881 flood erased. Menard, in the county’s southwest corner, is unrelated to Menard County far to the north — this Menard is a small unincorporated crossing near the Mississippi.

ZIP Codes

• 62233 — Chester (county seat)
• 62278 — Red Bud
• 62286 — Sparta
• 62288 — Steeleville
• 62237 — Coulterville
• 62242 — Evansville
• 62272 — Percy
• 62277 — Prairie du Rocher
• 62241 — Ellis Grove
• 62217 — Baldwin
• 62292 — Tilden
• 62280 — Rockwood
• 62297 — Walsh
• 62261 — Modoc
• 62259 — Menard

Smaller unincorporated communities such as Kaskaskia, Ruma, Preston and Schuline use the ZIP code of the nearest post office town rather than a code of their own.

Geography

Randolph County lies where the Kaskaskia River meets the Mississippi, and its western edge follows the Mississippi’s American Bottom — a band of flat, fertile river-flat farmland below the bluffs. The eastern half of the county rises into rolling upland typical of Southern Illinois, drained by Mary’s River and several smaller Kaskaskia tributaries. The county borders Monroe County to the northwest, St. Clair County to the north, Washington County to the northeast, Perry County to the east, and Jackson County to the southeast. Across the Mississippi River, it also borders Perry County, Missouri to the south and Ste. Genevieve County, Missouri, to the southwest.

Demographics

Randolph County had 30,163 residents at the 2020 census, a density of about 52 people per square mile. Sparta and Chester are its two largest communities. Median household income in the county runs below the Illinois median of $80,306, consistent with the mostly rural, agricultural economy of Little Egypt counties. About 79% of residents live outside the county’s incorporated cities and villages.

Economy & Local Life

Corn, soybeans and livestock drive the rural economy outside the three cities. Chester is home to the Menard Correctional Center, one of Illinois’s oldest and largest maximum-security prisons, a major county employer. Sparta anchors light manufacturing and retail for the county’s northern half, while Red Bud serves farms and river-bottom communities along the Kaskaskia. Chester also draws visitors as the birthplace of Popeye creator E. C. Segar, marking the connection with a riverfront statue trail and an annual Popeye Picnic.

History

Randolph County was organized in 1795, the second county formed in the Illinois Territory, and takes its name from Edmund Randolph, the Virginia governor and first U.S. attorney general whose state ceded its western land claims to open the Northwest Territory. Kaskaskia served as the capital of the Illinois Territory and then the first state capital after Illinois joined the Union in 1818, before the seat of government moved to Vandalia in 1820. An 1881 Mississippi River flood cut a new channel that stranded Kaskaskia on the river’s west bank, physically separating it from the rest of Illinois — it remains the only piece of the state lying west of the Mississippi.

Getting There

Illinois Route 3 runs the length of the county along the Mississippi, and Illinois Route 4 and Route 150 connect its eastern towns.

• Sparta — 15 miles northeast of Chester
• Red Bud — 20 miles north of Chester
• Steeleville — 12 miles east of Chester
• St. Louis, Missouri — about 60 miles northwest of Chester

The nearest commercial airport is St. Louis Lambert International Airport, roughly an hour’s drive northwest.

Frequently Asked Questions

Where is Randolph County, Illinois?
It sits in Southern Illinois on the east bank of the Mississippi River, part of the region known locally as Little Egypt, roughly an hour southeast of St. Louis.

What is the population of Randolph County?
30,163 people at the 2020 census.

How big is Randolph County?
597 square miles (1,550 km2), of which 576 square miles is land and 22 square miles is water.

What is the county seat of Randolph County?
Chester is the county seat.

How many towns and villages are in Randolph County?
Three cities (Chester, Red Bud, Sparta), eleven villages, and roughly two dozen unincorporated communities.

What ZIP codes are in Randolph County?
Fifteen ZIP codes serve the county, including 62233 (Chester), 62278 (Red Bud), 62286 (Sparta) and 62288 (Steeleville).

Why is Kaskaskia in Illinois cut off from the rest of the state?
An 1881 Mississippi River flood carved a new channel that left the village of Kaskaskia stranded on the river’s Missouri-side bank — the only part of Illinois lying west of the Mississippi.

More counties in this state: Towns and villages in Illinois.