The county's namesake is James Pleasants, Jr., an esteemed former US Senator and Virginia Governor.

[3][4] On June 20, 1863, at the height of the Civil War, Pleasants County was one of fifty Virginia counties that entered the Union as the state of West Virginia.

In 1863, West Virginia's counties were divided into civil townships, with the intention of encouraging local government.

This proved impractical in the heavily rural state, and in 1872 the townships were converted into magisterial districts.

[5] Pleasants County was divided into six districts: Grant, Jefferson, Lafayette, McKim, Union, and Washington.

[13] As of the census of 2000, there were 7,514 people, 2,887 households, and 2,136 families living in the county.

22.90% of all households were made up of individuals, and 12.30% had someone living alone who was 65 years of age or older.

As of the 2010 United States census, there were 7,605 people, 2,861 households, and 2,021 families living in the county.

The county is also served by the Mid Ohio Valley Technical Institute, which offers vocational education in a variety of fields.

[20] However, from 1900 onwards the county has generally voted Republican except in strong Democratic election victories, and like all of West Virginia it has become rock-ribbed GOP in the twenty-first century as a consequence of de-unionization in the coal industry.