[2] The county was formed in 1847 and named for the military officer John C.

91.01% were non-Hispanic White, 0.17% were Black, 2.88% were Hispanic, 0.29% were Native American, 0.17% were Asian, 0.08% were Native Hawaiian or Pacific Islander and 5.42% were some other race or more than one race.

[12] As of the census[13] of 2000, there were 8,010 people, 3,199 households, and 2,242 families residing in the county.

26.30% of all households were made up of individuals, and 14.90% had someone living alone who was 65 years of age or older.

Fremont County is divided into thirteen townships: The population ranking of the following table is based on the 2020 census of Fremont County.

Starting with the 1944 election, the county has become a Republican Party stronghold, only failing to back a Republican presidential candidate in 1964 amidst Lyndon B. Johnson's national landslide.