Florida History: Once a year at the Olustee Battlefield Historic State Park outside of Macclenny in Baker County, citizens commemorate the largest Civil War battle in Florida. The Union campaign that climaxed in the Battle of Olustee (or Ocean Pond) began in February, 1864, when troops commanded by General Truman A. Seymour embarked at Hilton Head, S.C. Battle casualties amounted to 1,861 Union and 946 Confederate soldiers. In proportion to the number of troops involved, it was one of the bloodiest battles of the Civil War.