Saint Syagrius ((French) Saint Siacre) (died 600 AD) was a bishop of Autun. His feast day is August 27 (September 2 in some martyrologies).
He was bishop of Autun from around 560 until his death and travelled to Nanterre with Guntram for the baptism of Clotaire II. He provided hospitality to Saint Augustine of Canterbury on the latter's way to England. Pope Gregory I granted Syagrius the pallium and decreed that the bishops of Autun have precedence in France after the archbishop of Lyon.
His relics can be seen at Val-de-Grace in Paris.