From Japan to 1600: A Social and Economic History, by William Wayne Farris (U. Hawai‘i Press, 2009), pp. 184-186:
For the clergy, the Warring States Era was a time of intense competition for believers and confrontation with the military authorities. In general, the older sects in Nara and Kyoto lost out; Rinzai Zen became weaker with the collapse of the Muromachi bakufu. On the other hand, believers in Sōtō Zen, the Pure Land, and the Lotus Sutra increased greatly. Jesuits brought Roman Catholicism to Japan and they succeeded in making many converts. The emerging thought system, Shinto, chose its sacred texts and drew pilgrims to shrines at Ise and Mount Yoshida in Kyoto.
The fate of Enryakuji, headquarters to the Tendai faith, symbolized the hard times faced by older sects. Already in the 1400s, Enryakuji had begun to lose its lands to warriors and to lose revenues to Kyoto moneylenders. The Muromachi bakufu generally ignored the frequent demonstrations so frightening to the court in the twelfth century. Finally, in 1571 after the warlord Nobunaga had taken control of Kyoto, he had his troops surround Mount Hiei where the temple complex was situated and, shockingly, ordered them to burn the mountain, ending Enryakuji’s pretensions to independent political and economic power. One of the most venerable institutions in Japanese history had been reduced to cinders.
By contrast, Sōtō Zen expanded rapidly into the countryside between 1450 and 1590, primarily because of warrior patronage. Along the Japan Sea littoral, local “men of the province” founded new temples, even as prelates promised them salvation and worldly benefits. The population in Sōtō Zen monasteries and temples grew exponentially in the 1500s, partly because Buddhist monks ignored their behavioral precepts and served potential warrior patrons rice wine in elaborate rituals.
True Pure Land Buddhism benefited from the enlightened rule of its eighth head, Rennyo (1415–1499), who had five wives and twenty-seven children. He proselytized far and wide, writing hymns and pastoral letters to guide his followers. He was especially successful around his home temple Honganji near Kyoto, in eastern Honshu, and along the Japan Sea littoral. The families that became his followers formed congregations as grassroots units, and soon they were known for their cohesion. For example, during a famine, farm families would reserve grain for like-minded artisans and merchants. These congregations numbered between twenty and a thousand and met monthly for religious discussion and worship. They also received rules checking wild behavior, such as slandering other sects or attacking political leaders. By the early 1500s, True Pure Land Buddhism had emerged as a powerful religious organization.
Eventually, this sect came to be known as the “Single-minded” (Ikkō) school because of its adherents’ devotion to Amida Buddha. The cohesion of believers made them difficult for daimyo to control, and in 1488 between 100,000 and 200,000 of the faithful drove a warlord from his domain in Kaga located along the central Japan Sea. The Kaga devotees established an “estate of the Buddha,” resisting local warrior rents and labor dues. Like-minded local samurai willing to accept the new regime soon joined, sharing power with the Ikkō sectarians. Warrior armies failed to suppress the wayward province until 1580, slaughtering thirty to forty thousand religious soldiers in fierce battles.
Meanwhile, the focus moved to the Ikkō sect’s headquarters in the Kinai. When Honganji was burned in Kyoto in 1532, the tenth patriarch had it rebuilt as a fortification in Osaka and recruited an army of twenty thousand. Soon the Single-minded sect became a rallying point for all those opposing warrior rule. During the 1570s, the warlord Oda Nobunaga launched an all-out war against Honganji, using armored ships brimming with cannon to blockade the fortress. In the face of such overwhelming military power, the sect sued for peace on Nobunaga’s terms in 1580. Warrior power had triumphed over the religious network of the Single-minded sect.
The Lotus Sect was no less militant, espousing an ideology of “succeeding in this world.” Kyoto merchants and moneylenders joined in droves, because they felt that the Lotus Leagues, as they were known, helped to protect their profits. These radicals were also popular because they rejected the rents and labor dues imposed by warriors and clamored for the abrogation of urban taxes. Thousands of adherents chanting “Hail to the Lotus Sutra” demonstrated in the streets in long, circular processions, frightening commoners and aristocrats alike. Eventually they came to occupy twenty-one temples protected by moats and earthen walls.
Finally, between 1532 and 1536, the Lotus Leagues in Kyoto revolted against a powerful warrior in the region. Taking over the administration of the city, they kidnapped aristocrats, decided lawsuits, apprehended arsonists, and blocked rent payments. A type of “popular justice” meted out by the Lotus sectarians reigned in the city. In 1536, however, the tide turned against them, as Enryakuji, supported by samurai and the older Buddhist sects, counterattacked. Enryakuji and its allies burned many Lotus temples over a period of thirty-six hours. Survivors fled to the imperial grounds but were nevertheless killed there. Like the Single-minded believers, devotees of this urban religious movement succumbed to the forces of order.