In the year 3962 BBY, the Galactic Republic and the invading Mandalorian Neo-Crusaders clashed in a battle within the Zel system of the Inner Rim. This confrontation was a result of the Mandalorian Wars, initiated by the Mandalorians' incursion into Republic space. This battle was a component of the Mandalorian Triumph, a Mandalorian effort aimed at seizing Duro, a Core World. As part of this offensive, Mandalorian forces progressed from their own regions through the Ambria system and onward to Zel. The Mandalorians emerged as the victors in the Zel system, subsequently advancing to secure another victory at the planet of Commenor, maintaining their push toward the Core Worlds.
The reference book The Essential Atlas, authored by Daniel Wallace and Jason Fry and released in 2009, included a reference to the Zel system battle.