Otohiko Kaga (1929-), one of Japan's few Christian writers, is also a medical doctor. After graduating from the Faculty of Medicine at the University of Tokyo, he worked as a hospital and prison psychiatrist before taking up further studies in France. His writing debut came in 1967 with the long novel Furandoru no fuyu (Winter in Flanders). Senkoku (The Verdict) caused a sensation for its depiction of the actual lives of prisoners on death row. Since the late seventies, he has been a full-time writer. He converted to Catholicism under the influence of his friend Shusaku Endo (1923–96), also a writer.

1968 Ministry of Education Award for New Artists, for Winter in Flanders

1973 Tanizaki Jun'ichiro Prize, for Kaerazaru natsu (A Summer Long Gone)

1979 Japan Literary Grand Prize, for The Verdict

1986 Osaragi Jiro Prize, for Shitsugen (The Marsh)

1998 Ministry of Education Award for New Artists, for Eien no miyako (Eternal Capital)