Courtesy of Primitive Gallery

TIME: Was there a golden period of the ninja?

John Man: The height of the ninja was in the 16th century. They’d been evolving. As Japan descended into warlord-ism in the early Middle Ages, the areas where the ninja lived became more and more isolated. As the warlords scrapped over the rest of Japan, Iga and Koka developed their own commune system and self-defense and worked toward sort of a peak of ninja-ism toward the end of the 16th century, at which point their skills had been admired by everyone else, so they were finding employment in the rest of Japan as mercenaries. What happened, as Japan was unified under the great warlord Oda Nobunaga, they could not obviously be tolerated in a unified Japan. And so there were two great invasions of Iga and Koka which finally ended in the late 16th century with the complete takeover of the place and the end of the ninja as they had been for several centuries.

When did their mythological status grow? When did they become the shadowy men in black we now know of?

Yes, the great myth. In fact, they recommend in the ninja museums, which you can go to in Iga and Koka today, that black was not perhaps the best costume to use in nighttime — dark navy blue was better.

After 1600 when they became almost redundant, a few of them — some 200 or 300 — were taken on by the shogun as secret police. That’s not enough to give them much of an occupation, so some of them realized that in order for their skills not to be lost, they had better be recorded. Naturally enough, spies being spies, not much was recorded at all. So it was only after they became virtually redundant that they recorded their ways in three or four manuals. That’s really how we come to know anything much about how they actually worked.

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