Ninja's, often thought of as the world's first special forces, were prominent throughout Japanese warfare in the 15th, 16th, and 17th centuries. Centered mainly in the Iga and Koga province, ninjas trained under the supervision of the shonin (village leader).
In order to enter a home, a ninja used foldable saws (to break down doors), handclaws (to climb walls), flotation shoes (to walk across a moat), and disguises (usually as a yamabushi monk or a zen monk). Contrary to popular opinion, ninjas did not always dress in black.
Once inside the home, the ninja used many techniques to move and listen secretly. They used irogome (colored rice) to leave messages for future ninjas or some other ally. To listen in on a conversation, ninjas used a small tube that could be used to listen through walls. Then, to retreat, the ninja used smoke "grenades" and flash "grenades".
As for the assassin aspect of ninjas, their main weapon was a short sword with shuriken (throwing stars) hidden in the hilt. Other weapons include makibashi (caltrops filled with poison), a traditional bow, and a shinobi-gama (a sickle with a chain attached).
There were some female ninjas, although they were used less frequently.
For more information, readMilitary History Magazine (March 2006): Intrigue (Ninjas)
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