Greene County, the 11th county formed in Georgia, was created in 1786. Originally part of Washington County, Greene County was named for Revolutionary War hero General Nathaniel Greene.

The county has five municipalities, the largest of which is Greensboro, the county seat. The others are Siloam, Union Point, White Plains, and Woodville. Union Point is at the intersection of two separate railroad lines, and was originally called Scruggsville.

The top floor of the Greene County courthouse was built as a Masonic Lodge by arrangement with the county. The courthouse was constructed in 1848-1849.

The county has a consolidated school system with neighboring Taliaferro County.

There are several historical figures of note from Greene County. Thomas P. Janes was the first Commissioner of Agriculture in Georgia; William C. Dawson was a judge, a U.S. congressman and senator; George Foster Pierce was a Methodist bishop who served as the first president of Wesleyan College and later as president of Emory; and Peter Early was a state senator, congressman and Governor of Georgia.

There are two houses on Lick Skillet Road in Greensboro that are reputed to be haunted. At Ducaro Hall, built in 1837, footsteps can be heard late at night. At Early Hill, built in 1840, two ghosts appear. One is a man who sits in the rocking chair on the front porch; the other is a small girl who wanders upstairs and in the backyard.