Ichikishimahime-no-mikoto and Benzaiten
Around the Heian and Kamakura periods, as Shinto and Buddhism became mixed, Ichikishimahime-no-mikoto became to be seen as the same as the Buddhist goddess, Benzaiten.
Benzaiten was originally a Hindu goddess, Saraswati. It is said that the similarity of the two goddesses, both being a beautiful goddess related to water, made the two identified. Although Benzaiten was a water god, she was also believed as a god of performing arts. And also, since "zai" is pronounced the same as the kanji "zai (財)", that means treasures, she also became to be believed as the god of economic fortune. Ichikishimahime-no-mikoto became to have the same powers as well.
Numberless Bentenshas, dedicated to Benzaiten, were built around Japan. However, in the separation of Shinto from Buddhism, holding Buddhist rituals in shrines were forbidden, so shrines were no longer able to enshrine Benzaiten. Since Bentenshas were influenced more by Shinto, many of them changed their enshrined deities to Ichikishimahime-no-mikoto.