The founder, Teian, was born in 1539 (the 8th year of the Tenbun Period) in the Kuronuma district of Miura County, Sagami Province. At the age of six, he became a disciple of Gyoyo, his uncle, at Dairen-ji Temple in Odawara, which is a temple of the Jodo Shu (Pure Land Sect). In 1549, he entered the priesthood and received the religious precepts. Later, he moved with Gyoyo to Gugyo-ji Temple in Shimousa Province. Teian showed remarkable intelligence and mastered the esoteric practices of the Jodo Shu at his young age. Teian’s reputation reached the ears of Emperor Ogimachi and he granted Teian the title “Shoyo” in 1572 and ordered him to wear a koe robe (priest’s robe) when visiting the imperial palace. It was during this time that the relationship between Emperor Ogimachi and Teian started.

Following the Honnoji Incident in 1582 (the 10th year of the Tensho Period), Emperor Ogimachi heard Oda Nobunaga’s high regard for Teian and ordered him to hold a memorial service in his honor. Teian was then invited to the imperial palace to deliver a lecture on “Senjaku Shu (published by Honen in 1198)” and was bestowed with “Kujo’s kesa” (Buddhist robe) as a reward. This kesa has been passed down as a temple treasure. Additionally, Emperor Ogimachi donated Nijo New Imperial Palace to Teian and ordered him to establish the temple “Daiun-in” to commemorate Oda Nobunaga and his son Nobutada there.

Daiun-in maintained a strong connection with the imperial palace in the years that followed. Emperor Go-Yozei succeeded to the throne from Emperor Ogimachi and upheld a robust relationship with Daiun-in. In 1590 (the 18th year of the Tensho Period), Emperor Go-Yozei designated Daiun-in as a temple of imperial patronage and the following year, he bestowed Daiun-in with the imperial scroll, the name “Daiun-in” in “shinpitsu” (emperor’s handwriting). This was a prestigious recognition for the temple.