The Southern Frontier Defense Force is a border guard of sorts, stationed at Harmonia's southern frontier with the Grassland at Caleria. It is comprised of officers of many different skill types and background, including mercenaries and those trying to escape their past.
SFDF members usually protect the border or engage in espionage and other missions in the areas bordering Harmonia's south, such as the Grassland or the Dunan Republic. Members of the SFDF are not generally considered part of the main Harmonian army, but while serving in the Defense Force are expected to be loyal.
- Genso Suikoden Encyclopaedia (ISBN 4-575-16297-3), page 66
- Genso Suikoden Kiwami Encyclopedia, page 261