Julien was a sixth-century bishop of Vienne, located in modern-day France. Serving during the first half of the 500s, he held a significant ecclesiastical position, potentially acting as a metropolitan. Historical records indicate his participation in several important early church gatherings, including the Council of Lyon and the second Council of Orléans in 533. He is recognized as a saint within the Catholic tradition and is commemorated in various liturgical calendars.