Po Nudo was an Aqualish Ualaq male who served as a representative for his home planet, Ando, within the Galactic Republic's Senate. His time there coincided with the Trade Federation's invasion of the planet Naboo. A decade afterwards, he was present at a clandestine meeting on Geonosis, where he and various other senators pledged allegiance to Sith Lord Count Dooku and subsequently departed from the Republic to establish the Confederacy of Independent Systems. In the immediate aftermath of this assembly, the Republic forces arrived, triggering the First Battle of Geonosis. This conflict marked the commencement of the Clone Wars between the Republic and the Separatists, compelling Nudo to escape from the planet.
During the Clone Wars, the Aqualish senator severed ties with the Republic and became a member of the Separatist Council. His designated role was as the manager of the Hyper-Communications Cartel, which functioned as an alternative communication network to the Republic's HoloNet. As the war progressed, Nudo and the rest of the council were concealed on Utapau, under the protection of the cyborg General Grievous. Following the Battle of Coruscant and the demise of Dooku, Grievous informed the council of his orders to relocate them to a different planet. However, their meeting was disrupted by Jedi Master Obi-Wan Kenobi, who launched an attack on Grievous, initiating the Battle of Utapau. Amidst the chaos, the council fled and were moved to the volcanic world of Mustafar. As the Clone Wars neared their end, Darth Sidious—who had secretly orchestrated the Separatist movement while also serving as the Republic's Supreme Chancellor—dispatched his new apprentice Darth Vader to Mustafar, where he murdered the entire Separatist council, including Nudo.
Decades later, Nudo was recognized as a noteworthy Aqualish figure in "Species From A to Z," a survival guide distributed by Carson Teva during the New Republic Era.
Po Nudo's initial appearance was in the 1999 film, Star Wars: Episode I The Phantom Menace. This film served as the inaugural installment of the Star Wars prequel trilogy. He was portrayed by an uncredited extra, and his character remained unnamed at that time. The character was first given a name in the Star Wars Legends novel Cloak of Deception in 2001, authored by James Luceno. Paul Nicholson, an extra, played Po Nudo in the 2005 film Star Wars: Episode III Revenge of the Sith.
During the early development of Revenge of the Sith, Ryan Church, the concept design supervisor, created a piece of concept art. This art depicted an alternative outcome for Po Nudo during the Mission to Mustafar sequence, which was ultimately unused in the final version of the film. In Church's concept, Skywalker used his lightsaber to sever Nudo's head, instead of simply cutting him down, before proceeding to kill the remaining Separatist leaders.
In the 2018 reference book Star Wars: The Complete Visual Dictionary, New Edition, on page 127, Nudo's name is written incorrectly as "Po Nudu."