The town's name derives from a grove of walnut trees near its original site. It was officially incorporated in 1905 by the Georgia General Assembly . However, the community's roots trace back further; around 1875, a one-room schoolhouse was established adjacent to Walnut Grove Baptist Church, serving as a cornerstone for early settlers.

Modern Walnut Grove continues to balance growth with its historical roots. The town has seen the establishment of a new historic council and boasts one of Georgia's few all-women city councils, reflecting its progressive community spirit . With ongoing developments like the new Grove Park and a commitment to preserving its heritage, Walnut Grove exemplifies the harmonious blend of tradition and progress.