[3] The county is named for explorer Meriwether Lewis, who died and was buried at Grinder's Stand near Hohenwald in 1809.

The bill for its creation was proposed by Powhatan Gordon in the Tennessee State Senate.

[5] On October 7, 2009, a ceremony was held at the cemetery to commemorate the bicentennial of Lewis's death.

[7] As of the 2020 United States census, there were 12,582 people, 4,715 households, and 3,175 families residing in the county.

Historically, like all of secessionist Middle Tennessee, Lewis County was overwhelmingly Democratic.

Since then, however, like much of the rural white South, it has become overwhelmingly Republican due to opposition to the Democratic Party's liberal views on social issues.