Gamma Demetrius was a star system located near the Klingon Empire. In reference stardate 1/5105.02 (circa 2218), the USS Sentry encountered the IKV Devisor near Gamma Demetrius, becoming the first Federation Starfleet vessel to meet with a Klingon warship. A short battle marked their first contact. (ST reference: Spaceflight Chronology, FASA RPG modules: The Four Years War, The Federation, The Klingons)