Formed January 19, 1839 (79th county)
Marshall County (11,744), Lacon (1,881), Henry (2,318)
A Georgian Revival style courthouse built of red brick was constructed in 1854. It was added on to in 1884 and remodeled in 1950. It is sited on Prairie Street between 5th and 6th streets. Prairie Street is Illinois State Highway 26. Comegys & Brother and Card & Haggard combined on the designs. The grounds feature a tank and veteran memorials. Marshall County was formed on January 19, 1839 out of Putnam County 79th county with Lacon as the only county seat. United States Supreme Court Chief Justice John Marshall is the inspiration for the county’s name. The county seat name comes from a book by C. C. Colton.
Marshall County government consists of a sheriff, an attorney, a coroner, a clerk, a treasurer, and an assessor (executive). It has 20 Board Members (legislative.) Twenty Circuit Court Judges serve Marshall, Peoria, Putnam, Stark, and Tazewell counties and a court clerk serves Marshall County (judicial.) Marshall County is located in north central Illinois north of Peoria, Illinois and southwest of Chicago, Illinois. The Illinois River flows through the middle of the county. The county center is 11.3 miles East of Lacon nearer Varna. The county is surrounded clockwise by Putnam, La Salle, Woodford, Peoria, Stark, and Bureau counties.
The area of the county is 386 square miles. It is 74 out of 102 in the state. It ranks 85 out of 102 in population in the state. It has a density of 30.4 persons per square mile making it 73 out of 102 in the state. Marshall County has 66.6% of its population in its incorporated areas. Interstate Highway 39 goes north to south through the eastern part of the county from La Salle County to Woodford County. The county is a zig-zag shape. Lacon is in the western half on the east bank of the Illinois River. Henry is near the northern border on the west bank of the Illinois River. Lacon is the county seat and Henry is the largest city. Lacon is 16.0% of the county population while Henry is 19.7% of the county population. The county seat is pronounced LAE-KON. This county is in the Peoria Metropolitan Statistical Area.
Henry
Hopewell
Lacon
La Rose
Sparland
Toluca
Varna
Washburn
Wenona