Yes. Historical sources document covert agents called shinobi no mono performing espionage, infiltration, and sabotage during the Sengoku period. The word 'ninja' (a Chinese reading of the same characters as shinobi) became standard in the 20th century.

Did ninja and samurai fight each other?

Sometimes — when employed by opposing sides. But the more common relationship was that daimyo employed shinobi agents alongside their regular samurai forces. Nobunaga used Iga shinobi; Tokugawa Ieyasu had a famous shinobi connection to Hattori Hanzo.

Is Hattori Hanzo a real historical person?

Yes. Hattori Hanzo (c. 1542-1596) was a real historical figure who served Tokugawa Ieyasu. He is associated with the Iga shinobi and reportedly helped Ieyasu escape danger after Nobunaga's death at Honno-ji. The supernatural skills attributed to him in popular culture are legend.

Ninja vs Samurai: What Is the Actual Difference?

Samurai and ninja were different things. The confusion comes partly from popular culture combining them and partly because the relationship between the two in real Japanese history was more complex than a simple opposition.

Samurai: An Open Military Class

Samurai were a legal hereditary class — people born into a designated social stratum with specific rights, obligations, and markers of status (the right to wear swords, to have a surname, to serve a lord officially). They performed military service openly, with identity known to allies and enemies. [history]

Their role in the Sengoku period included fighting, yes — but also administration, logistics, and diplomacy. In the Edo period, most samurai were administrators who had not fought in anyone’s lifetime. [history]

Ninja: Covert Agents

Shinobi (忍び, the historical term — “ninja” is a 20th-century popularisation) were covert agents conducting espionage, infiltration, sabotage, and sometimes assassination. They operated across normal social boundaries — often disguised as other classes, working in secret. [history]

Shinobi are documented in historical sources from the Sengoku period. They were employed by daimyō who needed intelligence about enemy castles, troop movements, and political situations. The two main regions associated with shinobi training and organisation were Iga and Koka provinces (modern Mie and Shiga Prefectures). [history]

The 1681 manual Shoninki (“True Record of Shinobi”) codifies shinobi methods — infiltration techniques, disguise, psychology, and operations. It treats the subject as a professional craft. [history]

The Relationship

The two were not necessarily opposed. Daimyō employed both — open samurai armies for formal warfare, shinobi agents for intelligence and special operations. Oda Nobunaga used Iga shinobi. Tokugawa Ieyasu had a close connection to Hattori Hanzo, an Iga shinobi leader who served him. [history]

Some shinobi came from samurai families. The distinction was role, not necessarily birth class. [history]

What Is Legend

The popular image of ninja — black-clad, superhuman, flying through the air, using exotic weapons — is largely a 20th-century construction from popular fiction, martial arts schools, and entertainment. Historical shinobi were covert agents whose main tools were disguise, patience, local knowledge, and careful planning — not supernatural abilities. [legend]

The black outfit (shinobi shozoku) popularised in films was not the standard historical dress. Historical accounts suggest shinobi often used ordinary civilian clothing as the best disguise. [legend]