Pope Sixtus IV. From a miniature prefixed to the dedication copy of Platina's Lives of the Popes in the Vatican Library 202 Battista Sforza, Duchess of Urbino, second wife of Duke Federigo. From the bust by Francesco Laurana in the Bargello, Florence. (Photo Alinari) 214 Federigo of Urbino and his Family. Detail from the picture by Justus of Ghent, in the Palazzo Ducale, Urbino. (From the Ducal Collection.) (Photo Alinari) 216 Lorenzo de' Medici. From the fresco by Ghirlandaio in S. Trinità, Florence. (Photo Alinari) 238 Giuliano de' Medici. (Photo Alinari) 240 The Birth of Venus. Supposed portrait of Simonetta Cattaneo--mistress of Giuliano de' Medici. Detail from the picture by Sandro Botticelli in the Uffizi Gallery, Florence. (Photo Alinari) 242 Astorgio III. de' Manfredi. From the picture by Scaletti in the Pinacoteca of Faenza 258 Federigo di Montefeltro. After the picture by Justus of Ghent, once in the Ducal Collection at Urbino, now in the Palazzo Barberini in Rome. (Photo Anderson) 266 The Contessa Palma of Urbino. After the portrait by Piero della Francesca in the National Gallery 280 Guidobaldo I. From a picture in the Colonna Gallery in Rome 296 Caterina Sforza. After the picture by Marco Palmezzani in the Pinacoteca of Forlì. (Photo Alinari) 306 Isabella of Aragon. After the drawing by Beltraffio in the Biblioteca Ambrogiana, Milan. (Photo Anderson) 310 Pope Alexander VI. Detail from a fresco by Pinturicchio in the Borgia apartments of the Vatican, Rome 320 "Diva Julia." From a bronze medal _ca._ 1482 by L'Antico in the British Museum. By the courtesy of G.F. Hill, Esq. 330 Cesare Borgia. From a medal _ca._ 1500 in the British Museum. By the courtesy of G.F. Hill, Esq. 330 Julius II as Cardinal. From a medal in the British Museum. By the courtesy of G.F. Hill, Esq. 330 St. Catherine of Alexandria. Supposed portrait of Lucrezia Borgia by Pinturicchio. Detail from a fresco in the Borgia apartments of the Vatican, Rome. (Photo Anderson) 344 Bianca, daughter of Ludovico Sforza. After the picture by Ambrogio de' Predis in the Biblioteca Ambrogiana, Milan. (Photo Anderson) 352 Cesare Borgia as the Emperor. Detail from the fresco of the Disputa of S. Catherine in the Borgia apartments of the Vatican. (Photo Anderson) 364 CHRONOLOGICAL TABLE CHAPTER I