[2] The legislature of the Republic of Texas authorized Leon County in 1846 from part of Robertson County, and named it in honor of Martín de León, the founder of Victoria, Texas.

However, local tradition holds that it is named for a yellow wolf of the region commonly called the león (Spanish for lion).

The 1886 Leon County Courthouse was designed by architect George Edwin Dickey of Houston, incorporating remnants of an earlier 1858 courthouse that was destroyed by fire.

As of the census[10] of 2000, 15,335 people, 6,189 households, and 4,511 families were residing in the county.

Leon County is so heavily Republican that in 2014 none of the statewide GOP nominees fell below 87 percent of the votes cast.