The Ruusan campaign was the last campaign of the New Sith Wars. The campaign also is referred to simply as the Battle of Ruusan, although that is also used to describe the seventh battle. They consisted of seven battles on the planet Ruusan that were stretched over a two year span from 1,002 BBY to 1,000 BBY.
During the campaign, the Galactic Republic's Army of Light was commanded by Jedi Lord Hoth, and the New Sith Empire's Brotherhood of Darkness was led by Skere Kaan, Dark Lord of the Sith. Throughout the course of the battles, additional reinforcements attempted to land on Ruusan, though many Jedi forces were destroyed by an orbiting Sith blockade and many Sith reinforcements were destroyed by the Republic Navy en route to Ruusan. Five of the seven battles were won by the Army of Light, although the first battle of Ruusan was an absolute victory for the Sith; the Republic's forces were utterly destroyed and not a single Republican escaped that battle alive.
The final battle led to the destruction of both the Brotherhood of Darkness and after thousands in the initial battle,a final hundred Jedi,who sacrificed themselves to force Lord Kaan to detonate his final superweapon, the thought bomb, underground in the caverns on Ruusan, taking himself and all Sith lords with him,instead of on,for instance,on a core world.This controversial decision and the enormous damage caused to the planet by the ongoing space, air and ground battles with ever changing fortune and the ecological aftereffects of the thought bomb lead to the Ruusan Reformation of Supreme Chancellor Tarsus Valorum and the Rule of Two of Darth Bane, who secretly arranged these course of events to wipe out the Brotherhood of Darkness and so start again with only his apprentice,to now conquer by stealth and deception.