In 23 BBY, Quenelle was a Human female who reigned over Nallastia as both its Margravine and, secretly, the Skull Queen; she was a direct descendant of Margrave Octan. During that same year, her daughter, Princess Calvaria, acting without Quenelle's knowledge, had Klay's parents kidnapped for alleged trespassing and violating Nallastia's sacred wildlife laws, imprisoning them within an energy field generated by ancient Trinity Stones via a wrongful decree. When Anakin Skywalker, an 18-year-old Jedi Padawan, crashed his starfighter on the moon, the Jedi Knights Obi-Wan Kenobi and Bultar Swan enlisted Quenelle's help in finding him. However, at her fortress, she discovered that Skywalker had befriended Klay and taken Calvaria as a hostage to secure the release of Klay's parents. At that point, Quenelle revealed her identity as the Skull Queen, rebuked her daughter, and joined Kenobi in a search for the Lost Stars of Nallastia, three ancient jewels capable of deactivating the energy field. These jewels were located inside the Cavern of Screaming Skulls within the jungle-covered moon, leading to the liberation of Klay's parents.
Later, during the celebratory events at the Queen's fortress, Groodo the Hutt, a shipbuilder from Esseles, seized control of a spaceport on nearby Fondor and took Calvaria as a hostage. To rescue Calvaria and retake the spaceport, Quenelle journeyed with Swan and the Jedi Masters Mace Windu and Kit Fisto. Their mission was successful, causing the avaricious Hutt and his accomplices—Hurlo Holowan and Senator Rodd of Fondor—to flee. Before Kenobi's return to Coruscant, Quenelle bid him farewell with a kiss, expressing her disappointment that she could not marry him.
Quenelle possessed a Nallastian rescue runner, the very salvage vessel in which she arrived to discuss salvage rights to the alleged ancient ship, the [Sun Runner](/article/sun_runner]. Her opponent in these salvage-rights negotiations was Senator Rodd. Swan, Kenobi, and Skywalker were all present, monitoring the negotiations.
Quenelle decreed death sentences for poachers who hunted Nallastian wildlife, which the Nallastians held as sacred; these creatures included species such as the venrap, grillik, and killspike.