The Ishiyama Hongan-ji War, taking place from 1570 to 1580 in Sengoku period Japan, was a ten-year campaign by lord Oda Nobunaga against a network of fortifications, temples, and communities belonging to the Ikkō-ikki, a powerful faction of Jōdo Shinshū Buddhist monks and peasants opposed to the rule of the samurai class. It centered on attempts to take down the Ikki's central base, the cathedral fortress of Ishiyama Hongan-ji, in what is today the city of Osaka. While Nobunaga and his allies led attacks on Ikki communities and fortifications in the nearby provinces, weakening the Hongan-ji's support structure, elements of his army remained camped outside the Hongan-ji, blocking supplies to the fortress and serving as scouts.