User blog comment:Master Sima Yi/New settings poll!/@comment-4513154-20120327075728/@comment-1153722-20120327080456

Even if that was the case, I don't see the problem. Imagine climbing around Japanese cities and seeing all the detailed ornaments. The different guards, the different culture. The term "ninja" wasn't used during Feudal Japan anyways so it wouldn't be named once in the game. And if the Assassins would be compared to ninja, Kōga would be a good Assassin headquarters.

Oh, and I'm not too sure if there would be hidden blades. The hidden blade was first used in the Middle East and later made its way to Europe after Altaïr's influence expanded the Brotherhood west of the Levant, but Shao Jun shows that the Chinese Assassins didn't have a hidden blade but used their own distinct weaponry. It can be assumed that the Japanese Assassins had none either... unless some western Assassins secretly traveled along with Europese missionaries to Japan during the mid 16th century and introduced the hidden blade to the Japanese Brotherhood...

By the way, there is also a little reference to Japan in Revelations. Altaïr mentions Cipango, an old name for Japan, during the "Lost Legacy" memory.