Takemikazuchi is a god that appears in Japanese mythology.
It is written as "建御雷之男神" or "建御雷神" in Kojiki (The Records of Ancient Matters), and as "武甕槌" or "武甕雷男神" in Nihonshoki (Chronicles of Japan). It may be written simply as "建雷命." It is also known as Takefutsu no Kami, or Toyofutsu no Kami. In addition, it is also called Kashima no Kami, because it is enshrined in Kashima-jingu Shrine (Kashima City, Ibaraki Prefecture).
Descriptions in Kojiki
In kamiumi (bearing gods between Izanagi and Izanami), Takemikazuchi was one of the three gods created out of the blood scattered on a rock from the root of Totsuka no tsurugi called 'Amenoohabari' when Izanagi beheaded Kagutsuchi (the kami of fire). In the narrative of Japanese Mythology called "Ashihara no Nakatsukuni heitei" (pacification of Ashihara no Nakatsukuni), it was described as a child of Itsunoohabari, which is also known as Amenoohabari.
In Ashihara no Nakatsukuni heitei, the god worked with Torinoiwakusufune no Kami to gain control of Araburu Kami (malignant gods) in Ashihara no Nakatsukuni (literally, "Central Land of Reed Plains," which refers to the human world), and won a fight with Takeminakata no Kami to conquer Ashihara no Nakatsukuni. Sumo is said to come from the fight with Takeminakata no Kami.
Furthermore, according to Jinmu tosei (story in Japanese myth about the first generation of the Imperial Family), the god dropped a Futsunomitama Sword, a part of himself, on a warehouse of Takakuraji (a person who appears in Japanese myth) to regain peace in confused Ashihara no Nakatsukuni.
The word, 'Mikazuchi' included in the name refers to lightening and Raijin (god of lightning) is also a god of a sword. Although the god is also known as Futsugami, it was originally different. According to "Nihonshoki," it was Futsunushi no Kami that descended with Takemikazuchi to Ashihara no Nakatsukuni. Futsunushi is a god enshrined in Katori-jingu Shrine.
Originally it was a god indigenous to Kashima and worshiped as a god of marine traffic. Kashima became an important region for Yamato sovereignty (the ancient Japan sovereignty) to debouch into the east. In addition, the Nakatomi clan in charge of religious services had long placed their faith in Kashima no Kami, Takemikazuchi, because it came from Joso region that covers Kashima. Therefore Takemikazuchi became an important god for Yamato sovereignty. When Kasuga-taisha Shrine (Nara City, Nara Prefecture) was established in Heijo-kyo (the ancient capital of Japan in current Nara), the Nakatomi clan called on Kashima no Kami for making a branch shrine and made the god its own ujigami (a guardian god or spirit of a particular place in the Shinto religion).
Worshiped as Raijin, god of sword, god of the art of Japanese archery, bushin (the god of war) and gunshin (the god of war), Takemikazuchi is enshrined in Kashima-jingu Shrine, Kasuga-taisha Shrine, and other Kashima-jinja Shrines and Kasuga-jinja Shrines nationwide.