It was named for David Meriwether, a general in the American Revolutionary War and member of Congress from Georgia.

[4] Meriwether County is part of the Atlanta-Sandy Springs-Roswell MSA.

Portions of the Pine Mountain Range are found in the southern parts of the county near the cities of Warm Springs and Manchester.

The western third of the county is located in the Middle Chattahoochee River-Lake Harding sub-basin of the same ACF River Basin.

[6] As of the 2020 United States census, there were 20,613 people, 8,051 households, and 5,504 families residing in the county.