The county was abolished in 1838, and later recreated in December 1874 from a portion of neighboring Lafayette County. [1]
Despite its proximity to Texas (which has no state personal income tax), Miller County residents are not exempt from Arkansas's state personal income tax unless they reside within the city limits of Texarkana. Miller County is also one of only two counties in Arkansas (along with Little River County) to be separated from all surrounding counties in the state by water — the Red River, in this case.
As of the census of 2000, there were 40,443 people, 15,637 households, and 11,086 families residing in the county. The population density was 65 people per square mile (25/km²). There were 17,727 housing units at an average density of 28 per square mile (11/km²). The racial makeup of the county was 74.02% White, 22.99% Black or African American, 0.63% Native American, 0.37% Asian, 0.02% Pacific Islander, 0.54% from other races, and 1.43% from two or more races. 1.58% of the population were Hispanic or Latino of any race.
There were 15,637 households out of which 34.00% had children under the age of 18 living with them, 50.90% were married couples living together, 16.00% had a female householder with no husband present, and 29.10% were non-families. 25.60% of all households were made up of individuals and 10.70% had someone living alone who was 65 years of age or older. The average household size was 2.52 and the average family size was 3.02.
In the county the population was spread out with 26.50% under the age of 18, 9.70% from 18 to 24, 28.60% from 25 to 44, 22.10% from 45 to 64, and 13.10% who were 65 years of age or older. The median age was 35 years. For every 100 females there were 95.00 males. For every 100 females age 18 and over, there were 90.10 males.
The median income for a household in the county was $30,951, and the median income for a family was $36,665. Males had a median income of $33,080 versus $21,376 for females. The per capita income for the county was $16,444. About 15.40% of families and 19.30% of the population were below the poverty line, including 27.90% of those under age 18 and 16.50% of those age 65 or over.