Quote Originally Posted by Steppe Merc
Because it was not Medieval. Try and think of this from a player that specializes in Eastern factions. It would be illogical for the Seljuqs, Mongols or Byzantines to try and sail to the America.
Lets remember that the discovery/conquest of the americas is at the end of the campaign, and that historically it was done by Spain, the dominant european power of the time. If your Seljuks, Mongols or Byzantines are by that time the dominant power, why shouldn't they go in for some aztec bullying?

Total historical accuracy would mean watching a documentary, not playing a game.