Ennin was a prominent Tendai Buddhist monk of the Heian period. A direct disciple of the founder of Tendai in Japan, Saichô, Ennin is known for his journey to China, and is credited with the establishment of numerous major temples.
He departed Japan for China as part of a formal embassy in 838, arriving at Mt. Wutai, the most famous Buddhist site in China, in 840. He settled in the Imperial capital of Chang'an for a time, but was expelled in 845 when the Chinese Court forced nearly all monks to return to lay life, as part of a series of anti-Buddhist edicts; he returned to Japan in 847. Following his return, he penned an account entitled "The Record of a Pilgrimage to China in Search of the Law."
Temples Ennin is credited with founding include the Enryaku-ji at Mt. Hiei; the Kôdaiju-in in Hiraizumi, which he established in 850 and which was later re-established as the famous Chûson-ji; and Sensô-ji in Edo, originally established in 645, but significantly restored and re-established by Ennin.
After his death, rivalries between his temple of Enryaku-ji, and Mii-dera, founded by Enchin, deepened, with each temple desiring to serve as the singular chief Tendai temple in Japan. His and Enchin's factions came to be known as Jimon and Sanmon, respectively.
A stone inscription referring to Ennin was discovered at the Fawang Temple in the Chinese city of Dengfeng in 2010. Along with an inscription related to I no Manari (aka Sei Shinsei) found in Xi'an, this is one of only a very few artifacts found in China which serve as concrete, explicit evidence of the Japanese kentôshi embassies to Tang Dynasty China.
- Watanabe Nobuyuki 渡辺延志, "Kentôshi Ennin ashiato Chûgoku de hakken" 「遣唐使「円仁」足跡 中国で発見」, Asahi Shimbun, 10 July 2010.
- Valerie Hansen, The Open Empire, New York: W.W. Norton & Company (2000), 240.