[citation needed] Over successive generations, a devotional cult arose around the figure of Prince Shōtoku for the protection of Japan, the Imperial Family, and for Buddhism.

Key religious figures such as Saichō, Shinran and others claimed inspiration or visions attributed to Prince Shōtoku.

In the late 6th century, Shōtoku led an enormous national project to promote Buddhism and he commissioned the construction of Shitennō-ji.

[7][5] The Buddhist temple was built in Settsu Province (present-day Osaka) after his military victory against the powerful Mononobe clan, for he is said[by whom?]

Archaeological excavations in 1939 have confirmed that Prince Shōtoku's palace, the Ikaruga no miya (斑鳩宮), stood in the eastern part of the current temple complex, where the Tō-in (東院) sits today.

[9] A popular quote attributed to Shōtoku that became foundational for Buddhist belief in Japan is translated as "The world is vain and illusory, and the Buddha's realm alone is true.

"[10] In his correspondence with Emperor Yang of Sui, Shōtoku's letter contains the earliest known written instance in which the Japanese archipelago is referred to by a term meaning "land of the rising sun."

[14] A legend claims that when Bodhidharma came to Japan, he met with Prince Shōtoku whilst under the guise of a starving beggar.

Instead of going ahead, Shōtoku gave him food, drink, and covered him with his purple garment, telling him to "lie in peace".

"[15] This legend is linked with the temple of Daruma-ji in Ōji, Nara, where a stone stupa was found underground, which is exceedingly rare.

[18] Two bills made with different types of materials and special inks with a face value of 100,000,000 (one hundred million yen) were also issued.