'Saijin' (祭神) is a term used to refer to a shrine and the god that is enshrined there.[1]
Today, many shrines either worship a deity from Japanese mythology or identify themselves with a deity from Japanese mythology.
Originally Shinto originated from the nature worship of the sea, mountains, and rivers as awe-inspiring Kintai objects, and in early shrines, the deities enshrined there had no particular name or were unidentified. Kiki (Shinto) (ja) and Manyoshu, only a few shrines, such as Ise Jingu and Sumiyoshi Shrine, mention the names of their deities. Most shrines were called by the name of the place where they were located or by the name of the shrine with "kami" appended. In the Enkishiki Jinmeicho, most shrines are only named by their company name, indicating that until around the early 10th century, when the Engishiki was compiled, the deities of most shrines were not specifically named.
From around the 10th century, the deity began to have specific divine virtues and functions, such as being the god of fire, the god of water, and the god of wood, in addition to being a Ujigami, Jinushi, or Gi no kami. Toward the end of the Kamakura period, the Kami-butsujaku theory, which was opposed to the Buddhism theory of honchi-tujaku, gained popularity mainly among the samurai class, and the deities were changed from place names and company names to those of Japanese mythology, or from "kami" to "kami" or "kami" to "kami". The deities were shifted to personal deities with names such as God (神 Kami), Life and Honor (命・尊 Inochi mikoto), Hiko (two spellings) (「彦・比古」), and Hime (「姫・媛・比売」). It was also widely practiced to bunrei (kanshin) powerful deities such as Inari and Hachiman and make them the main deities. This trend was carried out by Kokugakus in the late Edo period, who advocated Fukkoshinto and frequently quoted from Shinto scriptures. This spread to all village shrines and unranked shrines.
Therefore, the shrine's history remains questionable, and even in the Ronsha of shikinaisha, it is treated as a Ronsha with a very high probability of being a descendant due to folklore.
Usually, shrines worship several deities, and the deity enshrined as the main deity is called shuushin (主神)' or shuusaijin (主祭神), while other deities are called haishin (配神), haisishin (配祀神) or aidoshin (相殿神).
The division of deities into main and subordinate deities began to be practiced in the Meiji era (1868-1912) at government-owned shrines. The concept of "main deities and other deities" had existed before that time, and was called "Mae (前)" or "sodenjin (相殿神). The deities that are usually associated with the main deity, but there are other deities that have come to be enshrined together for various reasons. Some of the deities were enshrined at the same time as the main deity, others were added later, and some were originally deities that later replaced the main deity. Some shrines came to worship many distributing deities due to Shrine Merger Movement (ja) in the Meiji era.
Soden (also known as "combined hall") refers to a shaden in which multiple deities are enshrined, including the main deity. Soden-kami" refers to the deities enshrined in the shrine, but when there is a main deity and a subordinate deity, the subordinate deity is referred to as "Soden-kami.