The Seswenna Defense Forces was the Planetary Security Force for the Seswenna sector during the waning years of the Galactic Republic. The Human Ranulph Tarkin served in the Defense Forces and in 66 BBY, he led a successful campaign against the Delmaasi pirates. In 57 BBY, Tarkin was appointed as the Seswenna sector's Governor-General, which gave him command of the Defense Forces. He set about expanding the Defense Forces' capabilities, and under Tarkin's guidance it eventually became part of the larger Republic Outland Regions Security Force.