The is a lay-oriented Nichiren Buddhist group. It was founded by Tanaka Chigaku in 1880 as and renamed in 1884 before adopting its current name in 1914.
The lay Nichiren Buddhist organization now known as the Kokuchà «kai was founded by Tanaka Chigaku in 1880 as Rengekai ("Lotus Blossom Society") and renamed Risshà  Ankokukai in 1884 before adopting its current name in 1914. The group's modern name is derived from a passage in the ', a writing of the founder of Nichiren Buddhism, the 13th-century monk Nichiren, which reads .
Originally based in Yokohama, the group shifted its head office to Tokyo, Kyoto-Osaka, Kamakura and Miho, Shizuoka Prefecture before finally moving back to Tokyo. The group is currently based in Ichinoe, Edogawa-ku.
Among the group's principal teachings are to return to the teachings Nichiren and unite the various sects of Nichiren Buddhism. The group's teachings are characterized by a strong form of Nichirenism.
The group's sacred text is the Lotus Sutra and their main object of reverence is the , a mandala supposedly made by Nichiren on the island of Sado.
At its height in 1924, the group's membership was estimated at over 7000. The literary figures Takayama Chogyà « and Kenji Miyazawa were members of the Kokuchà «kai for a time. The group's official website continues to claim them, but they ultimately rejected Tanaka's nationalistic views.
The group's publications include the monthly magazines and .