The Kusanagi was commanded by Cagalli Yula Athha and Ledonir Kisaka and is best known as part of the Three Ship Alliance. Before the Archangel was officially commissioned as part of the Orb Union's Space Fleet, she was the Orb Union Space Fleet's official flagship.
She was launched to space from Earth during the Battle of Orb along with the Archangel. In space, the Eternal joined the two ships, forming the Three Ship Alliance. She helped end the Bloody Valentine War.
Towards the end of the Second Bloody Valentine War, after Chairman Gilbert Durandal revealed the Destiny Plan, the Kusanagi staged an attack on the Requiem space cannon. She and two other Izumo class ships fired their Lohengrins at the Requiem, only to have their attacks blocked by multiple positron deflector shields deployed over the superweapon's mouth. The Kusanagi ultimately survived the end of the war.