Shintōgo Kunimitsu (新藤五国光) was a Japanese swordsmith and was especially famous for making Tantō.
He was active during the Einin, Shōwa and Enkyō periods, generally acknowledged to be the teacher of master swordsmiths Masamune, Yukiimitsu and Norishige.
This is due to various similarities in style and workmanship that indicate that Masamune was almost certainly his student.
Book: Japanese Swords by Nobuo Ogasawara (tenth edition, printed 1986)
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