The last Raphael in private hands has been sold to a telephone bidder at Christie's for Â£18.5m. ($37.5m.) The superb portrait of Lorenzo de Medici, Duke of Urbino, painted to facilitate a shidduch, shows the Duke holding what is probably a portrait miniature of his future wife. The vivacity and boldness of the colors, together with the lively handling of the abundance of fabrics worn by the Duke, are typical of the style of the Renaissance master known as "the Prince of Painters." The Medici family ruled Florence between the 14th and 17th centuries and provided many of the greatest patrons of the High Renaissance. Donatello, Filippo Lippi, Botticelli, Raphael, Leonardo da Vinci and Michelangelo Buonarroti all received the patronage of the Medici family, one of the wealthiest in Europe. The Medici also held great power through a series of appointments, conquests and strategic marriages. One such appointment was that of Giovanni di Lorenzo de Medici (1475-1521), second son of Lorenzo the Magnificent, who was elected Pope Leo X in 1513. Seeking to consolidate the power of the Medicis, the Pope arranged for his nephew, Lorenzo, to be married to Madeleine de la Tour d'Auvergne, a cousin of Francois I, King of France, an important ally of the Vatican against the Holy Roman Empire. As neither the Duke nor the bride-to-be had met, an exchange of portraits was arranged in order that they could see what to expect. On May 2, 1518, the Duke was married in the chÃ¢teau of Amboise in France. Returning to Florence with his bride, their entry to the city was celebrated with a banquet at which Raphael's portrait of the Pope, now in the Uffizi, Florence, was exhibited. The couple had a child, Catherine de Medici, who went on to marry King Henry II of France, but less than a year after the marriage, Madeleine died. Lorenzo died soon afterwards in 1519. Raffaello Sanzio, called Raphael (1483-1520) was one of the most important artists of the High Renaissance and one of the most influential and accomplished painters in European history. He spent most of his life in Rome under the patronage of Julius II and his successor, Leo X, the uncle of Lorenzo Medici. The portrait is recorded in the possession of Cosmo de Medici, Grand Duke of Tuscany, in an inventory of 1553. During the 1800s, it was in the possession of two of the most prominent collectors of the 19th century: Lord Northwick (1769-1859), whose collection was offered at auction in 1859, and then the merchant Hollingworth Magniac (1786-1867) whose collection was sold at Christie's in 1892 when the Raphael went for 567 guineas.