Saburō Sakai was born on 25 August 1916 in Saga in Japan. Sakai was born into a family with immediate affiliation to samurai and their warrior legacies and whose ancestors (themselves samurai) had taken part in the Japanese invasions of Korea between 1592 to 1598, but who were later forced to take up a livelihood of farming following "haihan-chiken" in 1871. He is the third-born of four sons (his given name literally means "third son"), and had three sisters. Sakai was 11 when his father died, leaving his mother alone to raise seven children. With limited resources, Sakai was adopted by his maternal uncle, who financed his education in a Tokyo high school. However, Sakai failed to do well in his studies and was sent back to Saga after his second year.