Batman Ninja in Anime / Animation / Manga / Comics Posted December 2, 2017 It could be just a poor last minute translation. The Middle Ages revolved around a loss of knowledge because at the time the Library of Alexandria was the central hub of all that was known for that region of the world. The collapse of the Roman Empire along with the destruction of the Library caused a major societal setback. It's a bit more complex than that, but those are the two pivotal moments that set off a chain reaction of misfortune. Feudal Japan would be the more proper term for the movie.