Kasugasha

Japanese: 春日社 - かすがしゃ

...Moreover, Kofuku-ji Temple welcomed imperial envoys and held the great Vimalakirti ceremony every year, and the lectures at this ceremony were considered the gateway to becoming a high-ranking monk, which increased the temple's prestige. At the same time, the regent family (the Fujiwara clan's head priest) promoted the rituals at Kasuga Shrine and attempted to take possession of Yamato Province using its divine prestige, which prompted Kofuku-ji Temple to claim Kasuga Daimyojin as the god who protects Hosso Buddhism (protects Buddhism), and to deify and control Kasuga Shrine as the guardian deity. They demanded that the head priest begin holding eight lectures on the Lotus Sutra at the shrine's entrance in 1018 (Kannin 2), and using the idea of syncretism between Shinto and Buddhism, they preached about the original Buddha of the four Kasuga shrines....

From Yamato Province

...The latter theory assumes that Yamato's Kokubunji Temple was located at the southwest corner where Shimotsumichi and Yokooji crossed (currently Kokubunji Temple is located in Yagicho 2-chome, Kashihara City), and Yamato's Kokubunji Nunnery Temple was located in Hokkejicho, Kashihara City. As the power of the Fujiwara clan increased during the Heian period, Kofuku-ji Temple and Kasuga Shrine came to be revered as the clan temple and shrine of the Fujiwara clan. As the idea of syncretism between Shinto and Buddhism rose, Kofuku-ji Temple attempted to integrate with Kasuga Shrine (Kasuga Taisha Shrine), and by 1136 (Hōen 2), it had come to control Kasuga Shrine. ...

From Yoshida Shrine

…It enshrines Takemikazuchi, Iwainushi, Amenokoyane, and Himegami. This shrine was established as a shrine based on Kasuga Shrine in Nara. In other words, just as the Fujiwara clan established Oharano Shrine by inviting their clan deity, Kasuga Shrine, to Nagaoka-kyo, this shrine was also instituted in Heian-kyo. …

*Some of the terminology that refers to "Kasuga Shrine" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

Japanese:

…しかも，興福寺は勅使を迎えて大法会の維摩会を毎年執行，これの講問は高級僧侶の登竜門とされたため寺威があがった。おりから，摂関家(藤原氏氏長者)が春日社の祭祀を振興，これの神威をかりて大和国の領有をはかったことなどに刺激され，興福寺は春日大明神を法相宗擁護(仏法護持)の神といい，春日社の鎮守神化や支配をねらった。氏長者に強請して1018年(寛仁2)から法華八講会を社頭で修法，神仏習合思想をかりて春日四所明神の本地仏を教説した。…

【大和国】より

…後者の説では，大和の国分寺は下ッ道と横大路が交差する西南隅(現在，橿原市八木町2丁目に国分寺が所在している)に，大和の国分尼寺は橿原市法花寺町に想定している。　平安時代に入って藤原氏の勢力が増大するにつれ，興福寺と春日社は藤原氏の氏寺･氏社として尊信を受けるに至った。神仏習合思想の高揚とともに興福寺は春日社(春日大社)との一体化をはかり，1136年(保延2)ころには春日社を支配下に置くようになる。…