In the history of Japanese architecture, we considered the Amidado and Jyogyodo halls of the Heian period to be "Western Paradise Architecture". But, we find many elements of esoteric Buddhism in this architecture, and the space of the Hokkai-ji Amidado hall was constructed as a three-dimensional Vajradhatu Mandala. Such Amidado hallsappeared in the middle 12th century through the relationship between retired Emperors and Ninnaji-Omuro. The appearance of such Amidado halls was connected with the extension of the influence of Garbadhatu and Vajradhatu Mandalas upon the space of Buddhist architecture in the late Heian period, and this phenomenon was probably based on the devotion towards Amida Buddha in the Shingon Buddhist sect.
