Saint Stephen the Younger (Greek: Ἂγιος Στέφανος ὁ νέος, Hagios Stephanos ho neos; 713/715 – 28 November 764 or 765) was a Byzantine monk from Constantinople who became one of the leading opponents of the iconoclastic policies of Emperor Constantine V (r. 741–775). He was executed in 764, and became the most prominent iconodule martyr. His feast day is celebrated annually on 28 November. His hagiography, the Life of St. Stephen the Younger, is an important historical source.