Katori-jingu Shinto Shrine in Katori City, Chiba Prefecture, is one of the objects of worship in the Shihohai, a religious ritual performed by an emperor.

This shrine is the head shrine of about 400 Katori shrines standing mainly in the Kanto region, and enshrines the deity Futsunushi, which was depicted in Japanese myth as a guardian god when the Imperial Court was suppressing other powers in the country.  For the Imperial Court, which had completed the unification of Japan in 811 by subduing the Ainu, a rival force in eastern Japan, following the subjugation of rival forces in western Japan, the god Futsunushi was an absolute guardian.  Even in the successive samurai governments, thereafter, this guardian god continued to be worshipped as a war god.  Together with nearby Kashima-jingu Shinto Shrine in Ibaragi Prefecture, which enshrines the deity Takemikazuchi, they were believed to be the crucial guardian gods of the Imperial Court particularly for the battles against the Ainu. These events are long time ago though, the current Emperor Naruhito still performs a religious ritual called Shihohai early in the morning, January 1st, every year.  He prays to these guardian gods in every direction from the Imperial Palace for a good harvest and national security.  This ritual started in the 7^th century and has been kept since then gradually changing its form step by step.

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