Antoine Deynan was a Catholic priest from Nagasaki who lived during the late 16th century. As a member of the Franciscan order, he was part of a religious community during a period of increasing tension between the Japanese government and Christian missionaries. In 1597, he was arrested alongside twenty-five others for violating prohibitions against preaching the Christian faith. He was eventually executed by crucifixion in Nagasaki, becoming recognized as one of the 26 Martyrs of Japan.