BARBO, MARCO. - Cardinal, born in Venice around 1420, died in Rome on March 2, 1491. Related to Pope Paul II, whose surname he bore, he held the office of majordomo in the latter's household and, through him, was provided with ecclesiastical benefices, including in 1453 the abbacy of Rosazzo in Friuli. In September 1455, he was appointed by Callixtus III to the see of Treviso, from which he was transferred on September 17, 1464, by Paul II, to that of Vicenza. On September 18, he was created cardinal with the title of S. Marco, and on March 18, 1471, he became Patriarch of Aquileia, though detained in the Curia, he was never able to reside there. In 1472, Sixtus IV entrusted him with a legation to Germany, Hungary, and Poland, and later also to Denmark, Sweden, and Norway. Returning to Rome in October 1474, he was appointed on July 24, 1476, commendatory abbot of S. Croce di Sassovivo near Foligno. After all his attempts to restore the Benedictines of this abbey to the observance of their rule proved unsuccessful, he replaced them with the Olivetans.
On November 6, 1478, he became bishop of Palestrina, a city which he adorned with buildings and restorations. At the death of Sixtus IV, he was a candidate for the tiara, and then became a valuable aid to Innocent VIII. In February 1485, Barbo was given in commendam the priory of Pontida in the territory of Bergamo, and then, on December 3, that of S. Balbina in Rome, the conservation and enhancement of which he promoted with important restorations. He was esteemed for his integrity of life and nobility of character, and as a patron, he supported scholars and, in particular, the art of printing, then newly introduced to Rome. There he continued the works on the palace of S. Marco, now Palazzo Venezia, begun by Paul II, and erected the chapel of the Sacrament in the church of S. Marco, where he was later buried.
Letters exchanged between him and Matteo Vallaresco, archbishop of Zara, are preserved in Cod. Barb. lat. 1809. Cf. P. Paschini, Il carteggio fra M.B. e Giovanni Lorenzì, Vatican City 1948.