Richental, Ulrich von (c.1360-1437). Medium: pen and ink on paper. Date: 15th Century. Council of Constance 1414-18; held in Konstanz, Germany, to settle the Western Schism; the Greeks agreed to join in Communion with the Church of Rome; here the Catholics teach the Greeks the rites and rituals of the mass; Provenance: Private Collection. Photographic rights held by The Bridgeman Art Library.