During Attack of the Clones, there are repeated mentions of certain key events taking place "10 years ago" including (to the best of my memory) Sifo-Dias ordering the clone army from the Kaminoans , his death and also Count Dooku's turn to the Dark Side.
So what exactly happened that prompted him to order the clone army?
And on a related note, who did he order the clones for? Were they for the Republic, the Jedi or for Lord Sidious?
The film script makes it clear that the clones were ordered shortly after the events of Phantom Menace, specifically when it became clear that the Trade Federation was building a vast droid army.
AMIDALA is more beautiful now than she was ten years earlier when, as Queen, she was freeing her people from the yoke of the Trade Federation.
Mace Windu also stresses that the Jedi (having seen Darth Maul) are still in a tizzy about the potential re-emergence of the Sith;
MACE WINDU : It's been ten years, and the Sith still have not shown themselves. Do you think they are behind this?
Much of the back story of what happened "10 years ago" was covered in the Clone Wars TV Series.
The Season 6 (aka The Lost Missions) episode "The Lost One" reveals some of the missing back story to Sifo-Dyas and the creation of the Clone Army.
Master Sifo-Dyas foresaw the need for an army for the Republic to deal with an unknown threat, however, the Jedi Council did not agree. This led Sifo-Dyas to order the creation of the clone army on his own for the Republic, without approval of the Council or the Senate.
Darth Tyranus (aka Count Dooku) had Sifo-Dyas killed and was able to take over the project of creating the clone army, thus allowing Darth Sidious to ensure that the clones would be ultimately loyal to Sidious and would carry out Order 66 when necessary.
