First bishop of Toulouse, martyr (3rd century).
He preached first in what is now northern Spain and came to Toulouse, where he was martyred and buried. He was interrogated and refused to sacrifice to pagan gods. Then, according to the traditional account, he was tied to a bull which dragged him away, breaking his skull fatally. He was first buried in the cemetery outside the walls; then his body was translated to what is now the crypt of the fine church of S. Sernin. There too his successors are buried, together with many other relics of saints, some donated by Charlemagne. This church was an important pilgrimage centre, not least for some pilgrims to Compostela. Sernin was praised by Venantius Fortunatus and Gregory of Tours. His feast on 29 November is kept in Mozarabic as well as French calendars.
L. Duchesne, Fastes Episcopaux, i. 306–7;B.L.S., xi. 222; Saint-Sernin de Toulouse: trésors et metamorphoses (1990).