Colonization of Ohma - D ' un The colonization of the water moon Ohma - D ' un in 32 BBY was the result of a joint effort between the Gungans and the Human inhabitants of Naboo . The Gungan Boss Nass , initiator of the project , enlisted the help of his new allies , Queen Amidala and Obi - Wan Kenobi to bring the plants and creatures destined to populate the empty moon . While the mission was successful and led to the establishment of New Otoh Gunga , a majority of the colony was destroyed about ten years later when the Confederacy of Independent Systems used its poisonous swamp gas on the Gungans during the Battle of Ohma - D ' un . Prelude . In 32 BBY , the two sapient species that called Naboo their homeworld had forged an alliance after millennia of mutual mistrust : the Humans and Gungans had united their forces to reclaim their planet , which had been subjugated by the Trade Federation . In the ensuing period of prosperity and collaboration , the Gungan Boss Rugor Nass changed his long - standing policy of seclusion , opened the underwater capital of Otoh Gunga to offworld visitors . Because of that , the city gained more and more inhabitants , until it became threatened by overpopulation . Intent on preserving the ecological balance of Lake Paonga , in which the capital was located , and of the surrounding wilderness , Nass decided to establish a new colony on the water moon Ohma - D ' un , the largest of the three natural satellites in orbit around Naboo . The colonization . To help him handle that critical mission , Boss Nass turned to his new ally , Padmé Amidala , Queen of the Naboo . Under the guidance of Graf Zapalo , chief science advisor to Amidala , Gungan scientists and Naboo starship engineers worked together to come up with a number of new technologies . The crowning achievement of that collaboration was the " Mantaris " - class amphibious medium transport , a spaceworthy version of the traditional Gungan bongo submersible . In the mean time , the Gungans collected creatures and plants from Naboo and many other worlds such as Endor , Alderaan and Tatooine , hoping they would thrive on the empty water moon . Before the arrival of the Gungan colonists , the Gungan High Council asked Queen Amidala to travel to Ohma - D ' un in the company of the Jedi Knight Obi - Wan Kenobi , the Gungan Bombad General Jar Jar Binks and the astromech droid R2 - D2 . Together , they were to discover how the animals and plants they intended to introduce on the moon ' s surface would interact and how they would depend on each other to live . Once they obtained an ecologically sound environment , the Gungan settlers started to harvest valuable resources and use them to build the New Otoh Gunga . The physician Portillo , a citizen named Josie , a male librarian and the smuggler Toba were among the first settlers . At some point during the colonization process , a shipment of machine parts was to transit from Oxon City to Ohma - D ' un , but ultimately got hijacked by pirates before it could reach the moon installation . A group of heroes was subsequently assigned to escort all future shipments . After conducting a number of uneventful escorts , the heroes ended up facing another raid . With the help of one of the pirate fighters , who suddenly changed sides , the escort managed to take the pirate leader captive , forcing the entire group ' s surrender . Aftermath . Although the colonization effort was successful , the new Gungan moon did not enjoy its newfound propserity for long . In 21 . 8 BBY , while the Clone Wars were being fought throughout the galaxy , Ohma - D ' un was the scene of a battle bewteen the forces of the Galactic Republic and of the Confederacy of Independent Systems . While the Republic emerged victorious from that battle , the Gungan colony had been decimated by the Confederacy ' s deadly swamp gas .