Seminole County was created in 1920 from portions of Decatur and Early counties. It was named for the Seminole Indians who, faced with settlement, left their lands in the Chattahoochee River Valley and moved to the Florida Everglades. Led by their chief, Osceola, they fought two bloody frontier wars with the U.S. Army.
Donalsonville was named for Jonathan E. Donalson, a member of a prominent family who had pioneered Decatur County.
| Incorporated | Population | Total Area | |
| Seminole County | July 8, 1920 | 9,091 | 238.04 sq miles |
| Donalsonville | December 8, 1897 | 2,694 | 3.99 sq miles |
| Iron City | 1900 | 302 | .8 sq miles |
The creation of Lake Seminole behind the Jim Woodruff Lock and Dam inundated many acres in the southern portion of the county. What had largely been swampland was turned into a water recreation resource. Fairchild State Park, Reynoldsville State Park and Seminole State Park are all on the Seminole County side of the lake.
Seminole County is located directly above one of the largest known aquifers in the world.
The famous Three-Notch Road on Highway 39 runs through Seminole County. This road was built by a volunteer army in 1814, and was marked by three carved notches which are still visible on the trees today.
Downtown Donalsonville is the site for the annual Harvest Festival held in October. This is a celebration of the county’s top industry– agriculture. Arts and crafts, parade, food and competitions are highlights of this event.