This lightsaber, which brandished a blue blade, once belonged to Sifo-Dyas, a Jedi Master who possessed another lightsaber of similar color during his life. At the time of his demise, Sifo-Dyas was wielding this weapon, which was then left behind on the desert moon of Oba Diah, where Plo Koon discovered it.
Supreme Chancellor Valorum tasked Sifo-Dyas with a clandestine mission to parley with the Pyke Syndicate, and he carried this lightsaber during that assignment. Due to the schemes of Darth Sidious and Count Dooku, his shuttle was destroyed above the desert moon of Oba Diah. The Pykes gave Dooku the Jedi Master's remains, but they left the lightsaber within the destroyed spacecraft.
Towards the conclusion of the Clone Wars, the destroyed shuttle of Sifo-Dyas inexplicably transmitted a distress signal that was received by the Jedi Order. Master Plo Koon, accompanied by troopers from the 104th Battalion of the Republic Army, journeyed to the moon of Oba Diah to investigate the signal, where they located Sifo-Dyas's lightsaber in the wreckage. Given that the body was missing and Jedi records indicated that Sifo-Dyas's shuttle had been lost on Felucia rather than Oba-Diah, the Jedi Council initiated an investigation into the matter.