Born in 1543 in Yamashina, Kyoto, as the eldest son of the 10th monshu Shonnyo of Honganji. His childhood name was Chachamaru. In 1554, at age 11, he succeeded as the 11th monshu upon his father's sudden death. He married Nyoshunni, the niece of Takeda Shingen and daughter of the Minister of the Left Sanjo Kinrai, strengthening ties with the Takeda and pursuing marriage diplomacy with the Asakura, Azai, Miyoshi, and Mori clans. In September 1570, when Oda Nobunaga demanded that Honganji vacate the Ishiyama fortress and pay 5,000 kanmon in war levies, Kennyo declared Nobunaga an enemy of the Buddha and issued proclamations calling the faithful nationwide to arms. The resulting Ishiyama War lasted a decade. Ikko-ikki uprisings erupted simultaneously across Kaga, Echizen, Ise Nagashima, Kii, and Osaka, coordinating with the Mori navy, the Saika-shu, and the Negoro-shu to keep Nobunaga under relentless pressure. Military operations were directed by retainers like Shimotsuma Rairen, and the unity of the believers matched Japan's most formidable warlord blow for blow. But Nobunaga crushed the Ikko-ikki at Nagashima in 1574, Echizen in 1575, and finally Kaga in 1580, leaving Ishiyama isolated. In the third month of 1580, Kennyo accepted peace under an imperial edict from Emperor Ogimachi and withdrew from the Ishiyama Honganji fortress that had been the center of his movement for over 40 years. He relocated first to Saginomori Gobo in Kii, then to Kaizuka in Izumi, and in 1591 accepted a grant of land at Horikawa-Shichijo in Kyoto from Toyotomi Hideyoshi (the origin of the present-day Nishi Honganji). He died in Kyoto on November 24, 1592, at age 50.