Catholic Encyclopedia (1913)/Abundius
Abundius, an Italian bishop, b. at Thessalonica early in the fifth century; d. 469. He was the fourth Bishop of Como, in Italy, was present at the Council of Constantinople in 450, and took an active part against the Eutychian heresy at Chalcedon (451), where he was the representative of Pope Leo the Great. In 452 he also took part in the Council of Milan, convened to refute the same heresy. Abundius is one of those to whom the authorship of the "Te Deum" is occasionally attributed.
Westcott, in Dict. of Christ. Biogr., I, 10; Tillemont, Mem., X, 962.