Barbus, Marco an Italian prelate of the 15th century, was a native of Venice. He studied law at Padua, then went to Rome; was made bishop of Vicenza and archbishop of Aquilea, then cardinal, in 1457. He died at Rome, March 11, 1490. He wrote, Relatio Legationis in Partibus Septentiionalibus: — Decreta de Coelibatu a translation of the Responsiones Gennadii ad Maahometum. See Hoefer, Nouv. Biog. Genesale, s.v.