The Izum-class Large Cruiser was a large fold-capable carrier of the Robotech Expeditionary Force, and the predecessor of the Ikazuchi-class Large Cruiser. It was in service towards the end of the Second Robotech War, and during the Invid Invasion. Several vessels also participated in the early attempts of the Earth Defense Expedition to reclaim Earth from the Invid. It was seen briefly in flashbacks during Robotech: The New Generation.
During the Expeditionary Mission in deep space, The Robotech Expeditionary Force developed the Izum-class Large Cruiser after seeing the need for an effective planetary assault vessel. Shimada Enterprises, which had been a branch operating in deep, assisted Robotech engineers in designing the Izum-class by sacrificing most of its point defense systems in favor of quick-launch fighter bays, which were meant to overwhelm any alien threat during an invasion operation.
Several Izum-class vessels were deployed towards the end of the Second Robotech War to aid Earth against the Robotech Masters. During the early years of the Third Robotech War, they were part of the Earth Reclamation Force's fleets to reclaim Earth from the Invid. The attrition rate was horrendeous but by then, the slightly larger, more advanced Ikazuchi-class had been developed and deployed.