In this article, I shall explore how Gregory of Tours, the Gallic sixth-century historian and bishop, understood the persecution in Lugdunum (present-day Lyon) in 177. In Libri historiarum decem and Liber in gloria martyrum, Gregory briefly describes the persecution and names the martyrs, including Irenaeus, the bishop of Lugdunum. According to ancient historians, however, Irenaeus was not a martyr. It has been established that Gregory’s list of martyrs was derived from Eusebius’ Antiquorum martyriorum collectio, of which only fragments had survived in Gregory’s time. In addition, the translation of Eusebius’ Historia ecclesiastica into Latin by Rufinus altered the passage referring to Antiquorum martyriorum collectio. Given the corruption of texts that occurred during late antiquity and the early Middle Ages, another image of the persecution in Lugdunum formed in the eyes of Gregory.