Iga Ninja (伊賀忍者) are the practitioner of the school of Iga Ninjutsu (伊賀流; いがりゅう; iga ryū). These ninja are from the Iga Province.
The Iga are known for their long allegiance to the Tokugawa Family via the service of the Hattori Family, while also serving as watari ninja (渡り忍; transition ninja or migration ninja), or ninja who trade their services for employment. They are located in Iga Province in central Japan, which is present day Mie Prefecture.
In various ninja sources, the Iga Ninja were known to serve the Tokugawa Family, most notably the founder of the Tokugawa Shogunate, Ieyasu Tokugawa. Long ago, the Iga Province was under the rule of the Niki Family (仁木氏), who had the same ancestry as the Tokugawa, the Seiwa Genji (清和源氏), a branch family of the Minamoto. They were in league with the Ashikaga Shogunate and assisted Takeuji Ashikaga during the Northern-Southern Courts period (See The Kannō Disturbance and Yoriaki Niki (仁木頼章)). Speculations tell maintaining protection of the province was difficult. The Niki were also occupied by the Onin War; around Sengoku Jidai, Niki's rule over Iga ended and powerful local clans such as the Jōnin Three Houses took control. For the Seishin stories, The Niki continued to strongly serve the Ashikaga until they are destroyed.
It was possible that the Iga ninja were taxed harshly and dragged into service for the Mikawa Families. Basically, both Iga and Koga would get involved in the warring armies' political schemes that would support themselves the most.
- Main article: Tenshō Iga no Ran
Ninja activity elevated during the Warring States peroid. In 1582 (10th year of Tensho), after Akechi Mitsuhide killed Nobunaga Oda at the Honnoji Temple, Iga and Koga Ninja guided Ieyasu Tokugawa through secret mountain paths (Iga Pass; 伊賀越え) towards Mikawa Province.
These surnames (or regions. Could be both?) are mentioned during the Iga Revolt. Spelling may be incorrect
- 上林 (Kanbayashi)
- 郡村 (Gunmura)
- 市部 (Ichibe)
- 猪田 (Ida)
- 依那具 (Inagu)
- 四十九 (Shijyukyu)
These include folklore characters.