Gajo Sakamoto was born Masaki Sakamoto on December 1, 1895, in Itsukaichi-shi, Nishitama-gun (present-day Akiruno-shi), Tokyo. After studying painting for 5 years at a private art institute, the Kawabata Painting School, he followed the advice of famed cartoonist Ippei Okamoto and pursued a career as a professional manga artist. While working at several newspaper companies, he ran comic strips and contributed cartoons for newspapers, magazines, and comic anthologies. With Shigewo Miyawo and others, Sakamoto helped form the Doshin Manga-kai manga artists’ group. In January 1934, he started the serialization of Tank Tankuro in Yonen Club (from the Dainippon Yubenkai Kodansha publishing company), which made him a popular artist. The manga was published as a book in October 1935, and the Yonen Club serial lasted until December 1936. Other works from this period included Hora-gai Hora-taro and Janken Pon-chan. In 1939, Sakamoto served as a part-time employee for the government’s public relations department in Manchuria (Northeastern part of China) but returned home a year after Japan’s defeat. After his return, he continued his active career as a manga artist, working on titles such as Gara-gara Sensei, Bari-bari Hakase, and Genkotsu Osho as well as new stories for Tank Tankuro. Around this time, Sakamoto also became interested in the art of suiboku-ga or nan-ga (ink-and-wash painting) and studied Zen Buddhism. In 1956, the same year as the marriage of his first daughter, Sakamoto ended his career as a manga artist to devote himself entirely to Buddhism and suiboku-ga. In 1969, he received an award for his distinguished service to children’s culture from the Japan Children’s Writers’ Association. He died on August 8, 1973, at 77 years of age.