Hartford is located on a portion of land owned by Colonel Andrew Waggener, who in 1772 was given by King George III for his services in the French and Indian War. It was established as a town in 1853, and a coal mine was established the same year. Salt extraction began in 1856, by capitalists from Connecticut named Morgan Buckley and William Healey, who named the town for Hartford. The first post office was opened in 1858, and the community was incorporated in 1868.
There were 216 households out of which 31.5% had children under the age of 18 living with them, 52.8% were married couples living together, 11.1% had a female householder with no husband present, and 30.1% were non-families. 26.9% of all households were made up of individuals and 11.6% had someone living alone who was 65 years of age or older. The average household size was 2.40 and the average family size was 2.93.
In the town the population was spread out with 24.1% under the age of 18, 6.7% from 18 to 24, 30.3% from 25 to 44, 25.4% from 45 to 64, and 13.5% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 97.3 males. For every 100 females age 18 and over, there were 95.0 males.
The median income for a household in the town was $24,219, and the median income for a family was $31,528. Males had a median income of $25,469 versus $16,406 for females. The per capita income for the town was $11,661. About 14.3% of families and 16.9% of the population were below the poverty line, including 24.8% of those under age 18 and 12.0% of those age 65 or over.