[3] Fremont Township was organized in 1858, and named for John C. Frémont (1813–1890), an American explorer.

[4] According to the United States Census Bureau, the township has a total area of 35.9 square miles (93 km2), all land.

There were 139 housing units at an average density of 3.9 per square mile (1.5/km2).

The racial makeup of the township was 98.61% White, 0.28% Native American, 0.28% Asian, and 0.83% from two or more races.

18.5% of all households were made up of individuals, and 10.5% had someone living alone who was 65 years of age or older.