(Lat..Gairinus), abbot of Flavigny, in Burgundy, and thirty-first bishop of Autun, was born about 626. He took part in. the disputation in which his brother St. Leger, bishop of Autun, had engaged against Ebroina burgomaster of Neustria, and shared with him his alternatives of triumph and of persecution. Ebroin, having overcome his rivals, brought them before the tribunal, after having cut out their eyes. Guerin, being charged with complicity in the murder of Childeric II, was tied to a stake and stoned to death in 678. He is commemorated as a martyr on August 25 and October 2. See Hoefer, Nouv. Biog. Generale, s.v.