Despite Tsukuyomi's thin presence in the mythological narratives, his cult is attested unusually early and specifically on the small island of Iki, between Kyushu and the Korean peninsula, where a shrine to him, Tsukiyomi Jinja, is recorded among the important shrines listed in the tenth century Engishiki, the imperial compilation that catalogued officially recognized shrines and their ritual status across Japan. Iki's ancient inhabitants, the Iki clan, served the early Yamato court as professional diviners, and some scholars connect the island's prominent moon cult to this role, since the moon's regular phases made it a natural object of calendrical and divinatory attention for a community whose livelihood depended on reading omens and reckoning time.
A related shrine bearing the same name stands today in Kyoto, historically connected to the great Matsunoo Taisha, and tradition holds that the Kyoto shrine's founding is itself linked back to the older Iki cult, brought to the capital region as the Yamato state's religious geography expanded and centralized around the capital. Whatever the precise historical chain connecting these sites, honestly difficult to reconstruct in full from the fragmentary early sources, the persistence of dedicated shrines to a deity so nearly silent in the narrative mythology is a reminder that cult worship and mythological storytelling did not always develop at the same pace in early Japanese religion; a god who barely speaks in the Kojiki could still have held a real, named, ritually maintained place on the sacred map of the country.