A clash occurred on the planet of Diado in 19 BBY between the military of the Galactic Empire and the remaining soldiers of the Separatist holdouts. This confrontation was a component of the Sy Myrthian Insurrection. In this campaign, Imperial troops sought to expel the remaining Condeferate forces from the vicinity of both the planet Sy Myrth and the Kreetan Narrows area. This followed the Confederate's loss in the Clone Wars to the Galactic Republic, the predecessor to the Empire. Admiral Adar Tallon and General Jan Dodonna led the Imperial 12th Sector Army to victory over the Separatist holdouts' forces stationed at Diado. After this engagement, Imperial forces continued their winning streak, achieving victorious outcomes on the world Metalorn.
This conflict initially appeared within the pages of The Essential Guide to Warfare, a comprehensive guide released in 2012 that extensively covered various battles and wars throughout the galaxy. It was authored by both Jason Fry and Paul R. Urquhart.