The Battle on Duro stands out among the numerous engagements during Operation Durge's Lance, a strategic move by the Confederacy of Independent Systems to penetrate the Core during the period of the Clone Wars. This confrontation resulted in a significant triumph for the Confederacy.
At 0221 hours local time, Operation Durge's Lance successfully breached the outer defenses surrounding Duro. This involved the destruction of four Golan Arms defense platforms and three Acclamator-class ships—specifically, the Anvil, Coronet, and Bolide. Furthermore, two Dreadnaught-class heavy cruisers, namely the Prominence and Atrisian Iron, were also obliterated. Following this initial assault, the remaining Republic forces consisted of only four Acclamator-class vessels, a Victory-class Star Destroyer, and one additional Dreadnaught.
Jyvus Space City, one of Duro's largest orbital settlements, surrendered to the forces of the Confederate Navy. Battle droids and Neimoidian irregulars then converted the floating city into a command hub for the Office of the General. Simultaneously, Hoolidan Keggle, the Chief Representative Officer of Duro, disappeared. Intelligence suggested that Keggle had escaped from the city to the planet's surface below. The Confederate Navy's First and Third Fleets, the original force dispatched from Yag'Dhul, received supplies from Sullust and Thyferra. Techno Union ships deployed seismic EMP countermines to facilitate a straightforward offensive.
In response to the Confederate fleet, the Galactic Republic dispatched a squadron of Jedi starfighters along with two wings of V-19 Torrent starfighters. However, Vulture droids and droid tri-fighters swiftly overwhelmed the Republic's defensive efforts, succeeding in destroying an additional three assault ships. Subsequently, the Confederate forces strategically positioned themselves to sever all Republic supply lines originating from either Kuat or Nubia. With the capture of Jyvus Space City, the Confederacy gained the capability to disable the planetary shields safeguarding Duro. Separatist drop-fighters and capital ships initiated an orbital bombardment targeting industrial complexes on the planet's surface. This bombardment enabled troop landings, and over the course of a week of intense combat, city after city fell under Confederate control, culminating in Hoolidan Keggle's signing of General Grievous's terms of surrender to the Confederacy. The entire conflict lasted less than seven days.
The battle had catastrophic consequences for Duro's already delicate environment. The orbital bombardment compromised the remaining defenses against toxins, waste materials, and airborne pollutants. This made it impossible to inhabit Duro without protective equipment. Consequently, the surviving inhabitants of Duro were compelled to relocate from the planet's surface to the orbiting cities surrounding Duro.
In the aftermath of the battle, the Senate Bureau of Intelligence launched an investigation into the reasons for the Republic's defeat. One month later, Agent Inglemenn Barezz released a report revealing that falsified requisition orders had designated the three newly commissioned Venator-class Star Destroyers assigned to protect Duro as being on "shakedown cruises" at a secret location. In reality, the chairman of the Senate Action Subcommittee for Corellian Trade Spine Defense, the Rodian Senator Onaconda Farr, had redirected them to the Rodia-Ando front in the Mid Rim. It was further uncovered that Iseno Senator Ronet Coorr had diverted warships from Iseno, which were intended to support Duro, to Rodia after receiving millions of credits in bribes and promises of reconstruction contracts on Ando from Farr.
Following the report's publication, both Coorr and Farr relinquished their positions in the Senate. This triggered a public outcry against both the Senate and Rodians in general, with demands for granting the Supreme Chancellor absolute authority over the war effort and for placing Humans in command of fleets stationed near rival planets. A comprehensive inquiry into Senate Action Subcommittees was initiated with the goal of restructuring them. The Battle of Duro was considered one of General Grievous's most remarkable military achievements, leading many within the Republic to perceive him as an even greater threat than Count Dooku.
Duro would later be liberated by the Republic during the same year. Along with the victories at Commenor, and Balmorra, the battle was pivotal in expelling the Confederacy from its bases in the Core Worlds and the Colonies regions of the galaxy, marking the beginning of the Outer Rim Sieges.