Marshall is a city in and the county seat of Clark County, Illinois, United States, located approximately 20 miles (32 km) west of Terre Haute, Indiana. The population was 3,933 at the 2010 census.
Marshall is located at 39°23′34″N 87°41′37″W / 39.39278°N 87.69361°W / 39.39278; -87.69361 (39.392848, -87.693627).
According to the 2010 census, Marshall has a total area of 3.736 square miles (9.68 km), of which 3.72 square miles (9.63 km) (or 99.57%) is land and 0.016 square miles (0.04 km) (or 0.43%) is water.
As of the census of 2000, there were 3,771 people, 1,655 households, and 1,002 families residing in the city. The population density was 1,202.7 people per square mile (463.7/km²). There were 1,832 housing units at an average density of 584.3 per square mile (225.3/km²). The racial makeup of the city was 98.33% White, 0.29% African American, 0.13% Native American, 0.16% Asian, 0.11% Pacific Islander, 0.13% from other races, and 0.85% from two or more races. Hispanic or Latino of any race were 0.48% of the population.
There were 1,655 households out of which 28.3% had children under the age of 18 living with them, 45.2% were married couples living together, 12.0% had a female householder with no husband present, and 39.4% were non-families. 35.7% of all households were made up of individuals and 17.3% had someone living alone who was 65 years of age or older. The average household size was 2.21 and the average family size was 2.87.
In the city, the population was spread out with 23.7% under the age of 18, 8.0% from 18 to 24, 26.7% from 25 to 44, 19.8% from 45 to 64, and 21.9% who were 65 years of age or older. The median age was 39 years. For every 100 females, there were 84.4 males. For every 100 females age 18 and over, there were 80.9 males.
The median income for a household in the city was $33,413, and the median income for a family was $42,909. Males had a median income of $31,108 versus $21,144 for females. The per capita income for the city was $19,851. About 3.6% of families and 6.2% of the population were below the poverty line, including 6.6% of those under age 18 and 5.5% of those age 65 or over.