In Attack of the Clones, we see Obi-Wan talking to Lama Su about the clone army that has been created. Lama Su informs him that Master Sifo-Dyas is the Jedi who ordered the clone army for the Republic. Obi-Wan tells him that Sifo-Dyas died almost ten years ago.
What I want to know is, who in the Force is Sifo-Dyas? The question is left hanging from AOTC and never gets answered in ROTS. So i've been thinking.
It seems to me that, based on the movies, Sifo-Dyas could be one of two people--Darth Maul, or Qui-Gon Jinn. Both were trained Force users, so both could have masqueraded as a Jedi Master. Both died ten years prior to the events of AOTC. I think that it could be either of them.
Darth Maul, on the one hand, could possibly have been masquerading as a Jedi. Suppose that Palpatine pulled the same stunt on him as he did on Anakin, only far earlier in Maul's training, and had the young student conceal his conversion so that he could be an inside source on the Jedi's dealings. This way Maul could have ordered the clone army while masquerading as a Jedi Master, not too long before the events of TPM. However, i think this is a less likely possibility, because it doesn't get much more distinctive than red-and-black tatoos with devilish horns and a double-bladed lightsaber.
So i think Sifo-Dyas could more probably have been Qui-Gon Jinn. Qui-Gon was previously Dooku's apprentice. Perhaps Dooku was converted far earlier in the SW universe timeline than the movies imply, and persuaded Qui-Gon that a war was coming. He could have worked with Dooku to order the clone army using the name of Sifo-Dyas. This could also add some significance to Dooku's comment in AOTC to Obi-Wan that Qui-Gon would have helped him to battle the Republic.
What do you all think of that hypothesis? Any comments welcome.