-He actually lives in the 20th century AD, except no-one uses the gregorian calendar as europeans (apart from Vinland viking settlers) never came to America, leaving his people to chill for a couple extra centuries. Something bad clearly happened in the Old World for no-one to have ever come across the Atlantic, but it's not like the mesoamericans would know anything's amiss. :P
-He admires vikings. Thinks they're great warriors with unique view on life, even though these guys are clearly too pagan and hairy to be as civilized as the fair aztecs.
-Legitimately believes that aztecs are doing the rest of the world a solid by sacrificing war prisoners. Thinks that the blood keeps the sun moving in the sky and thus, the day that Aztec empire falls would be the end of the world.
-His idea of "chocolate" is a foaming beverage of chilly, maize and cocoa beans, sometimes flavored with honey or vanilla (the honey being a relatively new development in cocoa-drinking, coming forth from deepened trading relations to the maya).
-Actually pretty bright for a massive sack of muscle. :D Well-educated due to his upbringing with a fascination for that which is unknown and different.