Mempa system

The Battle of Mempa was one of the three major battles fought during the Klingon Civil War, in the Mempa system, between the forces loyal to Gowron and the forces of the House of Duras. The battle ended decisively in the Duras's favor, and Gowron's forces were sent into full retreat. (TNG: "Redemption II") However, Martok's bold leadership on that day kept the battle from turning into a complete rout. Miles O'Brien, posing as a Klingon named Pahash, claimed to have fought at Mempa. Ironically, in a way he had "fought" with Martok, since he had served on the USS Enterprise-D, which was nearby during the Klingon Civil War, supported Gowron, and ultimately aided in exposing the Duras Family. (DS9: "Apocalypse Rising")