The One-Day War represents a planetary dispute. It unfolded on Orto Plutonia during the era of the Clone Wars, pitting the Talz against the Pantoran species.
Following the events of the skirmish on Orto Plutonia, a Republic unit, comprised of clone troopers and led by Obi-Wan Kenobi, Anakin Skywalker, and Captain Rex, arrived on the planet. Their objective was to investigate the disappearance of the clone trooper garrison previously stationed at Glid Station. Accompanying them were C-3PO and R2-D2, along with a delegation of Pantoran officials, including Senator Riyo Chuchi and Chairman Chi Cho.
During their investigation, they discovered that both the Republic and Separatist bases had been ransacked by an unknown group. Skywalker and Kenobi tracked the clues to a nearby canyon, where they encountered the Talz, the planet's native population. Despite initial communication difficulties, Obi-Wan and Anakin conveyed their peaceful intentions and arranged a meeting between the Pantorans and the Talz. However, Chairman Chi Cho, who considered the Talz to be primitive, incited them, leading to the outbreak of war.
Skywalker and Kenobi urged Riyo Chuchi to seek a diplomatic solution. She contacted the Speaker of the Pantoran Assembly, who granted her the authority to negotiate peace and dismissed the Chairman's actions. Unfortunately, this intervention was somewhat delayed, as both the Talz and the Republic forces had already sustained losses, including Chi Cho. Senator Chuchi, accompanied by C-3PO, then approached the Talz and presented a spear and Chairman Cho's helmet before Thi-Sen. On behalf of the Pantorans, Chuchi acknowledged the Talz's sovereignty over Orto Plutonia, and both sides agreed to end the conflict.
The One-Day War, though not explicitly named, played a role in "Trespass," the fifteenth episode of the Star Wars: The Clone Wars television show's first season.