The Dyarchy was a small Sith principality that was located on the planet Byllura in the Grumani sector during the Republic Dark Age. It was led by the adolescent Sith Lord siblings Dromika and Quillan, with the Krevaaki Sith Lord Saaj Calician serving as its Regent. The Dyarchy started building its fleet in 1037 BBY as part of a planned expansionary campaign against the neighboring Daimanate. In 1032 BBY, the Jedi Knight Kerra Holt and the mercenary leader Brigadier Jarrow Rusher visited the planet following the Battle of Gazzari. Their actions brought about the collapse of the Dyarchy after Kerra kidnapped Quillan, which disrupted the worldwide mind-control ethernet the twins had used to enslave the planet's population. Their older sister and fellow Sith warlord then Arkadia Calimondra an