Reginald Horace Blyth (3 December 1898 – 28 October 1964) was an English author and devotee of Japanese culture.
Blyth was born in Essex, England, the son of a railway clerk. He was the only child of Horace and Henrietta Blyth. He attended Cleveland Road Primary School, in Ilford, then the County High School (later Ilford County High School). In 1916, at the height of World War I, he was imprisoned at Wormwood Scrubs, as a conscientious objector, before working on the Home Office Scheme at Princetown Work Centre in the former and future Dartmoor Prison. After the war he attended the University of London, where he read English and from which he graduated in 1923, with honours.
He adopted a vegetarian lifestyle which he maintained throughout his life. Blyth played the flute, made musical instruments, and taught himself several European languages. He was particularly fond of the music of J.S. Bach. In 1924, he received a teaching certificate from London Day Training College. The same year, he married Annie Bercovitch, a university friend. Some accounts say they moved to India, where he taught for a while until he became unhappy with British colonial rule. Other scholars dismiss this episode, claiming it to have been invented by Blyth's mentor Daisetz T. Suzuki.
In 1925, the Blyths moved to Korea (then under Japanese rule), where Blyth became Assistant Professor of English at Keijo University in Seoul. While in Korea, Blyth began to learn Japanese and Chinese, and studied Zen under the master Hanayama Taigi of Myōshin-ji Keijo Betsuin (Seoul). In Korea he started to read D. T. Suzuki's books about Zen. In 1933, he informally adopted a Korean student, paying for his studies in Korea and later at London University. His wife parted from him in 1934 and Blyth took one-year absence from the university in 1935, following her to England. After the divorce, Blyth returned to Korea in early 1936, leaving the adopted son with his ex-wife. The adopted son returned after World War II to Korea. In 1947 he was captured by North Korean soldiers; when he returned to the South, he was shot as a traitor by the South Korean army.