Irenaeus was a native of Smyrna in Asia Minor. In his Against Heresies (3.3.4) he recalls meeting Bishop Polycarp as a young boy. Like some other Christians from Asia Minor at that time, he then moved to Gaul, where he was ordained to presbyterate, probably by Bishop Photinus of Lyon. Jerome's account is based on the letter Irenaeus allegedly authored, which was partially preserved in Eusebius' Ecclesiastical History (5.4.1). In Eusebius' narrative, it follows another letter, quoted in length, which recapitulates the martyrdom of a group of Christians from Lyon, including Bishop Photinus. Eusebius dates these events to AD 177.
See also Efthymios Rizos, Cult of Saints, E00212 – http://csla.history.ox.ac.uk/record.php?recid=E00212