In the anime series Gundam Seed, the Izumo-class battleships were powerful warships of the Orb Union. Elements of their design were also used in the construction of the Earth Alliance's Archangel class assault ships, including their extremely powerful armament of "Lohengrin" positron blaster cannons and "Gottfried Mk. 71" dual beam cannons. One feature that remained unique to the Izumo class, however, was its modular design. This allowed them to jettison forward and rear modules containing most of the weaponry, and replace them with a separate forward module for atmospheric entry and launches back into space, where the weapon modules could be recovered. In addition, the Izumo class battleships had a large mobile suit hanger with room for more than 12 mobile suits, such as Orb's MBF-M1 Astray units. While they could not launch as quickly as suits carried by Archangel-class assault ships or Agamemmnon-class carriers, this compliment still made the Izumo class among the most powerful vessels of their time.

At least two Izumo-class ships were built by Orb, the Izumo and Kusanagi. The former was used by the Sahaku family, while the latter was commanded by Cagalli Yula Athha and Ledonir Kisaka, and became part of the Clyne Faction. It is unknown whether the other noble families of Orb also possess Izumo-class battleships, but it seems likely that they do. Izumo is named for a region of Japan supposedly where the Storm god Susanowo descended to earth when banished from heaven. Kusanagi is the second name of the sword, the Ame-no-Murakumo, which Susanowo pulled from the tail of the slain Yamato no Orochi and presented to his sister, the Sun goddess Amaterasu, as a reconciliation gift. Kusanagi is the sword of the Japanese Imperial regalia.