The Defender program represented a design initiative for starships during the early years of the New Republic. During this period, the newly formed Republic Engineering Corporation shipbuilding group conceived concepts for a compact Star Destroyer, a starfighter carrier, and an innovative snubfighter.
The starfighter variant was the only design that saw rapid development and limited deployment following the Battle of Endor. Despite its apparent effectiveness and reputation, it never achieved widespread use. The two capital ship designs faced setbacks due to Grand Admiral Thrawn's military campaigns and Operation Shadow Hand. These designs were ultimately integrated into the larger New Class Modernization Program, evolving into the Nebula-class Star Destroyer and the Defender-class assault carrier. Furthermore, their fundamental hull designs influenced the creation of the Endurance-class fleet carrier and the Majestic-class heavy cruiser.
The Defender program was first presented in the Cracken's Threat Dossier roleplaying game (RPG) supplement. Within this resource, it was established as the predecessor to the later New Class project, serving as the origin for two of the four core capital ship hull configurations within that broader initiative. The additional starfighter design was initially conceived for The DarkStryder Campaign RPG. In the Star Wars universe, the design was said to be an adaptation of an earlier model, while in reality, it drew inspiration from a late-era product within the Kenner toy line.