[5] DeKalb County was the site of several saltpeter mines, the main ingredient of gunpowder, and was obtained by leaching the earth from several local caves.

Overall Cave was named for Abraham Overall who moved from Luray, Virginia, and settled near the present site of Liberty in 1805.

[6] Unlike most of generally pro-Confederate Middle Tennessee, DeKalb County was seriously divided during the Civil War.

[7] In Tennessee's Ordinance of Secession referendum on June 8, 1861, DeKalb County voted to secede only by a margin of 833 to 642, which constituted the smallest margin by any county voting to secede.

[8] Earlier on February 9, 1861, DeKalb County voters had voted against holding a secession convention by a margin of 1,009 to 336.

[10] As of the 2020 United States census, there were 20,080 people, 7,704 households, and 5,401 families residing in the county.

When the school opened, Liberty High was closed and consolidated with DeKalb County beginning in September 1963.

Even before the rapid trend of the upland South away from the Democratic Party, DeKalb County was unusual for Middle Tennessee as it had significant Unionist sympathy[7] and was a competitive county for the GOP even at the height of the “Solid South” era.