[1] The county was created on December 19, 1793, and is named after General Joseph Warren, who was killed in the Battle of Bunker Hill.

[3] The north-to-northeastern quarter of Warren County, north of a line between the county's northwestern corner, Norwood, and Camak, is located in the Little River sub-basin of the Savannah River basin.

The southeastern quarter, from Camak in the north, and bordered by a northwest-to-southeast line running through Warrenton, is located in the Brier Creek sub-basin of the larger Savannah River basin.

The western half of the county, west of Warrenton, is located in the Upper Ogeechee River sub-basin of the Ogeechee River basin.

[4] As of the 2020 United States census, there were 5,215 people, 2,244 households, and 1,456 families residing in the county.