The Battle of Holleas was a major battle during the Clone Wars that pitted the armies of the Republic and the Confederacy of Independent Systems, as well as native freedom fighters for control of the planet, Holleas. Due to the world's rocky and swamp-like environments, it made travelling with massive weapons of war for both sides a hassle. Because of this setback, the factions suffered from high casualties that were not from combat. Severe weather disabled entire droid legions, and rare diseases killed many clones who were caught in the dangerous marshlands of Holleas.