Ninjas in popular culture

In the history of Japan, ninja (also known as shinobi) operated as spies, assassins, or thieves; they formed their own caste outside the usual feudal social categories such as lords, samurai, and serfs.

Some of the folk tales are based on historical figures, such as a daimyō (lord) challenging a ninja to prove his worth by stealing his pillow or weapon while he slept.

Such powers include flight, invisibility, shapeshifting, the ability to "split" into multiple bodies, the summoning of animals, and control over the five classical elements.

[citation needed] These notions stemmed from popular imagination regarding the ninja's mysterious status, as well as romantic ideas found in later Japanese art during the Edo period.

[citation needed] For example, Nakagawa Shoshujin, the 17th-century founder of Nakagawa-ryū, or martial art style, claimed in his own writings (Okufuji Monogatari) that he had the ability to transform into birds and animals.

Accounts exist of ninja being lifted into the air by kites, where they flew over hostile terrain and descended into or dropped bombs on enemy territory.

[citation needed] The kuji ("nine characters") is a concept originating from Taoism, where it was a string of nine words used in charms and incantations.

[6]: 24–27  The mudrā, a series of hand symbols representing different Buddhas, was applied to the kuji by Buddhists, possibly through the esoteric Mikkyō teachings.

[6]: 24–25  The yamabushi ascetics of Shugendō adopted this practice, using the hand gestures in spiritual, healing, and exorcism rituals.

Intended effects range from physical and mental concentration, to more incredible claims about rendering an opponent immobile, or even the casting of magical spells.

[10] During this second boom, some of the Japanese ninja-themed media were exported to several international markets such as Australia and Italy, but did not reach North America.

[17] A wave of ninja-themed films and television shows during the early-to-mid-1980s, especially those starring Sho Kosugi, led to "ninjamania" becoming a pop culture phenomenon across North America.

[23] Early ninja-themed home computer games included Saboteur (1985) and Ninja (1986), the latter featuring artwork resembling Sho Kosugi.

Series protagonist Joe Musashi was one of Sega's flagship characters in the late 1980s, along with Alex Kidd (before Sonic the Hedgehog).