To consider as well are the Index librorum prohibitorum and the Index of Prohibited Books of the Spanish Inquisition which applied to Spanish America (the first one to Portuguese America as well?) and appeared in the 16th century.

Also, it seems that in the 15th century Itzcoatl, a Mexica tlatoani, ordered the burning of many historical codices. I was not able to find earlier instances of banned books. Also, I do not know whether Indians in what is now the US or Canada had books (that could then be banned).