On October 21, 1570, Kennyo issued a manifesto to his believers, declaring that Nobunaga was a enemy of Buddhist who was trying to destroy Hongan-ji Temple, and suddenly attacked the Oda army that was deployed in Settsu Fukushima to attack the Miyoshi clan.
元亀元年（1570年）9月12日に顕如は「信長は本願寺を取り潰す仏敵である」として本願寺門徒に檄を飛ばし、三好氏攻略のために摂津福島に陣を敷いていた織田軍を突如攻撃した。