Bertin, Saint, a native of Constance, in Switzerland, was born about 597 of a noble family. He went with two companions in 633 to seek St. Omer at the abbey of Luxeuil. Bertin, elevated to the priesthood, in this retreat exercised himself in all the virtues;. and in 1639 he went to Terouane, near St. Omer, and became bishop of that place. There he spared neither time nor labor to instruct the people and to strengthen them.in the faith. St. Bertin had for a long time the direction of 150 friars; but at length, enfeebled by age and infirmities, he yielded to a successor, first Rigobert, then Orlefry, both of whom were his disciples. He died priest of Sithieu, at St. Omer, Sept. 5. 709, and was interred in the Church of St. Martin. His name was given to the monastery over which he had held control, and he is commemorated on Sept. 5. See Hoefer, Nouv. Biog. Generale, s.v.; Biog. Universelle, s.v.; Landon, Eccles. Dict. s.v.