Authentic documents that cover details about ninja missions and techniques were recently discovered in a town in western Japan. Japanese historians agree that these are important documents because they prove that the profession of ninja (those who secretly conducted espionage, sabotage and assassination) was something passed down for generations. Ninja clans were especially prevalent in the cities of Koka and Iga in Mie Prefecture but diminished during the Edo Period (1603-1868) until they no longer existed well into the Meiji Period (1868-1912).
150 items were found in home and a majority of these artifacts are instructional textbooks on how to properly conduct ninja practices. For instance, some books were information on poison, others on sleeping medicines and others still on advanced techniques in weaponry. Gunnery, horse riding and magic were among other skills ninja were expected to acquire.
Ninja made pledges to their local feudal domains and were called upon to fight in the event of an emergency. In times of peace or relative inactivity, many ninja were merchants or farmers and kept their activities as ninja classified even from family members and friends. Ninja often made an annual pilgrimage to their feudal domains for gunnery instruction and other purposes.
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