The Battle of the Montrosa Islands was a fight between the Alliance to Restore the Republic and the Galactic Empire on the agricultural planet of Reytha during the Galactic Civil War. It took place on the island chain in the Montrosa Ocean, the largest body of water on the planet. The battle was one of the most notable aquatic engagements in the War. Led by Darth Vader, Imperial troops defeated the Rebel navy forces guarding their garrison base.