Buddhism in Japan began teaching devotion to the "Lotus Sutra". Eventually, his disciples formed their own school of Nichiren Buddhism, which includes various sects that have their own interpretations of Nichiren's teachings. Nichiren Buddhism established the foundation of Japanese Buddhism in the thirteenth century. The school is known for its sociopolitical activism and looks to reform society through faith. In the Muromachi period, Zen, particularly the Rinzai school, obtained the help of the Ashikaga shogunate and the Emperor of Japan, and accomplished considerable development. After the Sengoku period of war, Japan was re-united in the Azuchi–Momoyama period. This decreased the power of Buddhism,
Risshū (Buddhism) the Shingon sect by decree of the Japanese government. Today only Tōshōdai-ji, which resisted the government measures, retains its identity as a Ritsu temple. Risshū (Buddhism) , also "Ritsu school", is one of the six schools of Nara Buddhism in Japan, noted for its use of the Vinaya textual framework of the Dharmaguptaka, one of the early schools of Buddhism. The Ritsu school was founded in Japan by the blind Chinese priest Jianzhen, better known by his Japanese name "Ganjin". Ganjin traveled to Japan at the request of Japanese priests, and established the Tōshōdai-ji in Nara. During the Kamakura period,