Gengo (914 - March 30, 995) was a Shingon Sect Buddhist monk who lived during the mid-Heian period. He was born into the Capital House of the Fujiwara clan and his father was First assistant musician (Uta no Suke) FUJIWARA no Shinsei. His priest title was Shingonbo.
He is also known as Enmeiin Sozu
After studying at a kangakuin (Fujiwara clan daigaku-besso (academic facility for nobles) or schools established at temples), he entered the Buddhist priesthood under Ganpo of Daigo-ji Temple before going on to study under Ichijo and Myochin. He was ordained by Junyu and Kanku, and in the year 968 he became one of the naikubu-juzenshi (the ten selected excellent priests for a Buddhist service in the Imperial Court) and gojiso (personal monk) to the crown prince. He attained the rank of Gon-Risshi (generally in Shingon sect, fifteenth-ranking Buddhist priest, literally, "supernumerary master of discipline") in the year 981, and that of Gon Daisozu (Junior prelate) in the year 983. Being well versed in the Ono and Hirosawa schools of the Shingon Sect, he authored numerous works including 'Gushi Kanjo Gishiki' as well as having numerous rainmaking miracles attributed to him. He left an autobiography entitled 'Genko Daisozu Jiden' (included in Zoku Gunsho Ruiju).