It was named after General Isaac Shelby, a hero in the American Revolutionary War and the first Governor of Kentucky.

Early settling in Shelby County began in 1848 in Galland's Grove.

In 1892, the construction of the present courthouse was begun, this time of stone and three storeys high.

The 1892 Shelby County Courthouse and the surrounding buildings are all listed in the National Register of Historic places effective September 23, 1994.

[12] As of the census[13] of 2000, there were 13,173 people, 5,173 households, and 3,703 families residing in the county.

25.20% of all households were made up of individuals, and 13.60% had someone living alone who was 65 years of age or older.

The population ranking of the following table is based on the 2020 census of Shelby County.