The cardinal who exposed the Donation of Constantine as a forgery
In 1433 the German churchman Nicholas of Cusa identified the Donation of Constantine as a forgery, a verdict Lorenzo Valla confirmed a few years later. The same polymath wrote on learned ignorance, pressed for calendar reform long before the Gregorian calendar, and was imprisoned by an Austrian duke.
Born in 1401 in Kues, in southwestern Germany, the son of a prosperous boat owner and ferryman, he studied at Heidelberg and took a doctorate in canon law at Padua in 1423, where he befriended the mathematician Paolo dal Pozzo Toscanelli. He became an expert in old manuscripts and textual criticism, which let him unmask not only the Donation but also the forged Pseudo-Isidorian Decretals. He also championed reform of the Julian calendar and Easter reckoning, a change that waited until 1582.
At the Council of Basel from 1432 he wrote The Catholic Concordance, balancing hierarchy with consent in church and empire, a book papal critics kept using long afterwards. Starting as a conciliarist, he came to back the pope, and in 1437 and 1438 he joined the mission to Constantinople to bring Byzantine leaders to the Council of Florence of 1439, whose union of the churches proved brief. He later said a moment of divine illumination aboard ship on the way back inspired On Learned Ignorance, finished on 12 February 1440.
Pope Nicholas V made him a cardinal and in 1450 Bishop of Brixen in Tyrol, and he spent 1450 to 1452 on a Great Legation of almost 3000 miles, preaching reform across German lands; many of his reforms failed. His attempts to reclaim diocesan revenues put him at odds with Duke Sigismund of Austria, who imprisoned him in 1460, earning the duke excommunication. Nicholas never returned to his bishopric.
Death came on 11 August 1464, at Todi, and he was buried in San Pietro in Vincoli in Rome, though his body was later lost. His heart lies in the chapel of the Cusanusstift in Kues, the charitable home he founded and endowed with his whole inheritance. The 600th anniversary of his birth in 2001 was marked on four continents.
Source: Nicholas of Cusa
