Tanaka Chigaku (????, 1861–1939) was a Japanese Buddhist scholar and preacher of Nichiren Buddhism, orator, writer and ultranationalist propagandist in the Meiji, Taisho and early Showa periods.
He is considered to be the father of Nichirenism, the fiercely ultranationalistic blend of Nichiren Buddhism and Japanese Nationalism espoused by such figures as Nissho Inoue, Kanji Ishiwara and Ikki Kita.
Notably, however, the children's writer, poet, and rural activist Kenji Miyazawa also idolized Tanaka, and both Miyazawa and Ishiwara joined his flagship organization, the Kokuchukai, in 1920.