“the wall-constructing emperors of undiscovered Chinas” this is a reference to the Great Wall of China. The primary purpose was always to protect the Chinese Empire from the Mongolians and other invaders. Most of the current Great Wall we see today was built in the Ming Dynasty (1368-1644) and is approximately 6000km long. (http://www.chinatravellers.com/Artcle_Show.asp?id=167)

jamón y queso is Spanish for ham and cheese