| Name | Marshall County |
| State | Illinois |
| FIPS Code | 17123 |
| County Seat | Lacon |
| Timezone | Central Standard Time (CST) |
| Population (2022) | 12,567 |
| Population Growth Rate(2000-2022) | -7.1% |
| Majority Ethnicity | White 99.2% |
| Public School Majority Ethnicity | White 92% |
| Partisan Voting Index | Republican:+15 |
| Unemployment Rate (December 2024) | 4.7% |
| Area Code(s) | 309 / 815 / 779 |
| Race/Ethnicity | Percentage of Population (2022) |
|---|---|
| White | 99.2% |
| African American | 0.6% |
| Hispanic | 0.01% |
| Asian | 0.19% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 0% |
| Race/Ethnicity | Percentage of Public School Students (2023) |
|---|---|
| White | 92.05% |
| African American | 1.21% |
| Hispanic | 4.21% |
| Asian | 0.05% |
| Native American | 0.05% |
| Hawaiin/Pacific Islander | 0.32% |