27 years ago - Uno is born as the champion of the ancient Q society, bred & manipulated to be the perfect man, the avatar of Quetzalcoatl.
3 years ago - 24-year-old Uno finishes his training & departs for America, posing as the deceased Dr. Curt Falconer, first becoming Aztek.
1 year ago - 26-year-old Uno ends his association with the Q society when he discovers that Lex Luthor is one of it's benefactors & joins the Watchtower. He sacrifices himself to stop Maggeddon, fufilling the Q society's prophecies.
A character created by Grant Morrison and Mark Millar is pretty much guaranteed to have a weird story, but Aztek stands out in the way he seems to be so straightforward, a deliberate attempt to craft an entirely new legacy. His origins were solid, his story new but immediately familiar. He seemed to fit quite neatly into Morrison's Justice League, even though he wasn't a member for long, and using the battle against Maggeddon as the culmination of his purpose completed his legend neatly.
I've never quite understood why he was a blonde white guy, though. If any character should be Hispanic, it's Aztek.