The ichinomiya of Satsuma Province

What the Japanese sources say

Two shrines, Nitta Jinja (新田神社) and Hirakiki Jinja (枚聞神社), are described as the ichinomiya, the first-ranked shrine, of Satsuma Province.

For Hirakiki Jinja, the Kagoshima Prefectural Shrine Agency says that “the Engishiki (a law code completed in 927 that lists official shrines) records it as Hirakiki Jinja of Ei District, Satsuma Province” and that it has “long been the ichinomiya of Satsuma Province, receiving the deep reverence of the imperial court generation after generation”. Ibusuki City also calls it “the ichinomiya of Satsuma Province”, and says it is held by tradition to have been founded in the first year of Wadō (708).

Nitta Jinja displays “Nitta Jinja, Ichinomiya of Satsuma Province” on its own website, but it gives no source name and no date for the claim to that title. Its principal deity is Ninigi no Mikoto, and its grounds contain an imperial mausoleum (可愛山陵).

— A difference of character can be read here: Hirakiki’s standing comes from the ancient imperial court, as a shrine listed in the Engishiki and raised in court rank, while Nitta rose later, from the medieval period onward, through the imperial mausoleum and the worship of Hachiman (as Nitta-gū) (this site’s view).

Written from Japanese sources, each quoted. The Japanese page has the same discussion with the original wording.