In the mirror universe, the ISS Nobunaga was a Constitution-class starship modeled after the USS Defiant. Its construction was ordered by Empress Hoshi Sato I due to renewed rebellion activity. The vessel was equipped by Commander Charles Tucker III with a prefix code that would allow the Empress to take control of the ship through subspace. However, while the Nobunaga was stationed at Beta Nairobi, Tucker gave the code to a clone of Jonathan Archer, who had joined the rebellion against the Empress. Archer then used the Nobunaga in strikes against the Empire. (ENT - Mirror Universe short story: "Nobunaga")
- The ship may have been named for the mirror counterpart of Oda Nobunaga, who began the unification of Japan in the late 16th century.