Emperors Heizei and Saga visited here and dedicated sutras as patrons of the temple. In honor of these dedications, the temple and town were renamed after them, using their names Hirajō and Mishō. Thus people call the temple Heijōzan Kanjizaiji of Mishō Town. At one time the temple included 48 sub-temples but was burned and restored by Munetoshi Date, the daimyō of Uwajima in 1679. When it was renovated more recently, local parishioners must have decided to end the fear of fire once and for all — the hondō is now made of concrete.

The funa-gata (boat-shaped) prayer to Amida that was written by Kōbō Daishi. Legend says that after carving the statues of Amida, Kannon, and Yakushi, he had a piece of the wood remaining. On it he carved the prayer Namu Amida Budtsu, Praise Amida Buddha, in raised letters with a fancy border and grass at the bottom. When ink is spread over it and the wood block is used to imprint something, it looks like a typical stone marker that one would see along the side of the road. The temple imprints many items with a more recent copy of the wood block (the original is considered too valuable to risk) and sells them to henro. They are believed to be effective against disease and have supposedly cured blindness, heart disease, and allowed a mute to speak. In addition, a woman who wears a piece of cloth imprinted from this block around her belly will have an easy pregnancy.

When the Taira (Heike) clan was defeated by the Minamoto (Genji) clan in the late 12th century battles that put the Minamoto in power and moved the capital to Kamakura, the Heike retreated here and lived out their lives as refuges.

Frederick Starr mentions a 5-storeyed pagoda here and says that it is the mausoleum of Emperor Heijo.

As an aside, Ehime Prefecture (Iyo Province) is known for the production of Iyo oranges and orange trees can be seen all along the coastline.