[3] The county was organized in 1799 and is named for Daniel Smith, a Revolutionary War veteran who made the first map of Tennessee and served as a United States senator.

[1] The location of the county seat was hotly contested between Bledsoesborough (near modern Dixon Springs) and William Walton's ferry and tavern at the confluence of the Caney Fork and the Cumberland River.

In 1804, voters chose Walton's site, and a town, named Carthage, was platted the following year.

Piper Cave, located near Monoville, contains the poorly preserved remnants of dozens of saltpeter leaching vats.

[5] The county is located in a transition area between the rugged Highland Rim to the east and the flatter Nashville Basin to the west.

The Caney Fork has its confluence with the Cumberland River in Carthage; these are the primary waterways flowing through the county.

However, while the county was Carthage resident Al Gore's fourth strongest statewide in his 2000 presidential bid, he failed to win an increasingly Republican Tennessee.

Since then, Smith County has swung hard towards the Republican Party similar to the rest of the state outside of Memphis and Nashville.