I'd think it should be something like the Holy Latin Empire.
Also, maybe as a counterpart to the Draka's preference for impalement as a punishment, the Spaniards use burning at the stake as their go-to punishment. Also, Faith would be more important for them than Race I imagine. I can also foresee them picking up some influence from the native tribes like the Inca or Aztecs, sorta like the Pagan/Indian fads of the Draka, with military ranks and such being taken from the Aztecs perhaps.
If they have a world domination ideology like Canon Draka, it would definitely be religiously motivated. And if we give them ubertech like the Draka had, I'd go with either Biotech or Ancient-Aliens BS, probably discovered from the same spot where Indie took the Crystal Skulls.