Kanrei - Spirit of Sugawara

...The Gion Festival in Kyoto is also essentially based on the belief in the divine spirit, and its original name was Gion Goryoe (abbreviated as Gion-e). According to the legend of Yasaka Shrine (Gionsha), when an epidemic broke out across the country in 869 (Jogan 11), people feared it to be a curse from the deity enshrined, Gozu Tenno, and on June 7 of that year, 66 spears were erected, one for each province in the country, and a divine festival was held, and on the 14th of the same month, a portable shrine was brought into Shinsen-en and a Goryoe ceremony was held. In addition, the belief in the appeasement of the vengeful spirit (Suga no Kanrei) of Sugawara no Michizane, who died in Dazaifu, Kyushu, in 903 (Engi 3), developed independently as Tenjin belief while combining with the belief in the divine spirit and the belief in the thunder god, and gave birth to Tenjin shrines in various places, including Kitanosha (Kitano Tenmangu) in Kyoto. After the Kamakura period, military commanders who met tragic ends were also included among the goryo deities, and a new aspect of goryo faith was born. In these cases, many goryo deities were given the name "Goro" because the word "goryo" sounds similar, and the shrines were also named "Gorosha," and Kamakura Gongorosha (Goryo Shrine) is one good example of this.

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

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…京都の祇園祭（ぎおんまつり）もその本質はあくまでも御霊信仰にあり，本来の名称は〈祇園御霊会〉(略して祇園会)であって，八坂神社(祇園社)の社伝では869年(貞観11)に天下に悪疫が流行したので人々は祭神の牛頭天王（ごずてんのう）のたたりとみてこれを恐れ，同年6月7日，全国の国数に応じた66本の鉾を立てて神祭を修め，同月14日には神輿を神泉苑に入れて御霊会を営んだのが起りであるという。また，903年(延喜3)に九州の大宰府で死んだ菅原道真の怨霊(菅霊（かんれい）)を鎮めまつる信仰も，御霊信仰や雷神信仰と結びつきながら天神信仰として独自の発達を遂げ，京都の北野社(北野天満宮)をはじめとする各地の天神社を生んだ。　鎌倉時代以降には，非運な最期を遂げた武将たちも御霊神の中に加わるようになって御霊信仰に新生面が出たが，その場合は御霊の音が似ているために〈五郎（ごろう）〉の名を冠した御霊神が多く，社名も〈五郎社〉で，鎌倉権五郎社(御霊神社)はその好例の一つである。…

※「菅霊」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報