Actually, they didn't do anything in feudal Japan. There is no historical basis for the existence of the Mythical "Ninja" as they appear in modern western myth. There was the Shinjen, rogue Samurai of the shogunates that where displaced whenever the Emperor changed hands (Usually by Klingon Promotion) the Ryukku islands, which where under martial law so they had to come up with the techniques, and weapons to hide their resistance that are now associated with "Ninjas" and the Ronin, who were lone masterless Bushi who wandered until they found a Shogun to fight for, and had no organization. All of these were combined into what we now know as the Ninja along with the uniform which was made up in the 20th century. And I know what the Wikis say, not to mention modern "Ninjitsu Masters" who made up the mystique and took a mix of contemporary, modern, and self made materials to make it look good. There was never any such thing, (Or they were so good, that they were never documented until after the Edo period.)
Actually, they didn't do anything in feudal Japan. There is no historical basis for the existence of the Mythical "Ninja" as they appear in modern western myth. There was the Shinjen, rogue Samurai of the shogunates that where displaced whenever the Emperor changed hands (Usually by Klingon Promotion) the Ryukku islands, which where under martial law so they had to come up with the techniques, and weapons to hide their resistance that are now associated with "Ninjas" and the Ronin, who were lone masterless Bushi who wandered until they found a Shogun to fight for, and had no organization. All of these were combined into what we now know as the Ninja along with the uniform which was made up in the 20th century. And I know what the Wikis say, not to mention modern "Ninjitsu Masters" who made up the mystique and took a mix of contemporary, modern, and self made materials to make it look good. There was never any such thing, (Or they were so good, that they were never documented until after the Edo period.)