Orto Plutonia was a frigid planet located in the Pantora system of the Outer Rim Territories' Sujimis sector. It was orbited by the moon Pantora, which was long believed to be the only inhabited world in the system. It was the homeworld of the Talz species, but was considered to be a protectorate of Pantora until the presence of the Talz was discovered during the Clone Wars. The Pantoran Assembly gave formal recognition to the sovereignty of the Talz over Orto Plutonia following a brief war between the Talz and the Pantorans. Shortly after the Battle of Yavin, the Rebel Alliance hid its fleet in the planet's orbit.
A desolate planet covered in ice wastelands, tors, and snowy canyons, Orto Plutonia was located in the Sujimis sector's Pantora system, at the edge of the Outer Rim Territories close to Wild Space. The planet maintained a breathable atmosphere as well as a frigid climate, and orbited a single star. Far from any major trade routes, Orto Plutonia itself was rare to visits, with its moon Pantora serving as the center of political life in the sector.
In 21 BBY, a force of Republic clone troopers under the leadership of Obi-Wan Kenobi, Anakin Skywalker, and Captain Rex landed on Orto Plutonia to investigate the disappearance of a local clone trooper force. With them were C-3PO and R2-D2, and a party of Pantoran dignitaries including Senator Riyo Chuchi and Chairman Chi Cho. Believing that there was no sentient life on Orto Plutonia, Chi Cho declared to the Republic leaders that, since it was within the boundaries of the Pantora system, Plutonia was technically considered Pantoran territory. Kenobi told Chairman Cho that the decision would be for the Galactic Senate to decide.
A search of the local area revealed that both Republic and Separatist troops had been destroyed, raising suspicion of a third party being involved. Further investigation led the Jedi to meet the Talz, a sentient species native to the moon, who had destroyed the forces from both sides in self-defense. Despite the language barrier, Obi-Wan and Anakin managed to establish that their mission was for peace, and they arranged a meeting between the Pantorans and the Talz. The Talz chieftain, Thi-Sen, asked that the Galactic Republic leave them in peace and withdraw all presence from Orto Plutonia. However, Chi Cho refused to accept the Talz as a sentient species and declared Plutonia as sovereign Pantoran property, provoking a war. In order to gain sanctity for his actions, he declared it to be an internal affair of Pantora.
Afterwards, Chi Cho and his escort were ambushed by a Talz war party, forcing them to fight. The Republic forces led by Rex, although reluctant to involve themselves in the war, defended Cho from the attackers. Following a drawn-out skirmish, Chairman Cho was severely weakened by a spear in his back. Skywalker, Kenobi, and Senator Chuchi arrived just in time to save Cho, Rex and the remaining escort from being overrun, but even with his last breath, Cho insisted on killing the Talz for the "good" of his people as his final command. Chuchi saw reason and informed him of the Assembly's decision to negotiate peace with the Talz. After short negotiations, Orto Plutonia was left to the Talz.