The Umanian War for Independence was an extremely short war fought between the Trade Federation and the Umanians trying to gain their independence from Federation rule. The Trade Federation, recently defeated at Naboo were in serious financial trouble. On the verge of bankruptcy Nute Gunray took drastic measures. Over the years the Trade Federation had gained control of many planets that they did not directly rule; they called them "colonies." During their financial distress they tried to squeeze every last cent out of the colonies. However, one such colony, Uman Rai, didn't take kindly to higher taxes and the desecration of some of their holy lands. The Umanians revolted and took control of the battle droid garrison.
This was a slap to the face to many high ranking Neimoidians who instantly demanded that Viceroy Gunray take action, and take action he did. He put OOM-10 in command of a sizable army and sent him to Uman Rai to put down the rebellion. As he landed near Port Royale he learned of an army massing at the nearby canyon. He marched his army to meet the rebels, which led to the Battle of Port Royale. The Trade Federation won the battle and began to march to the new Umanian capitol of Uman Rai.
As the droid army marched through Isis Pass they were ambushed by a large and well trained army of Umanian warriors led by Iscarrd Veston. The droid army was devastated and OOM-10 was destroyed. Nute Gunray decided that sending another army would prove too costly and abandoned the campaign. The Umanians won their independence. A new regime took control of all of Uman Rai after the short war; it was called the Republic of Uman Rai.