Frederick Barbarossa in Italy, 45. The siege of Crema, 50. Rival popes, 53. Imperial campaigns and reverses, 54. Frederick once more aggressive, 57. Battle of Legnano; peace of Constance, 58. Death of Frederick; his successor, 60. Growing power of the nobility, 61. CHAPTER III THE NORMANS IN SICILY (787-1204 A.D.) 63 The Normans in France, 65. The Normans come to Italy, 68. Capture of the pope; Robert Guiscard, 69. Conquest of Sicily; Eastern invasions, 72. Roger, great count of Sicily, 76. Roger II, 77. William the Bad (_il Malo_), 81. William the Good, 81. Norman influence, 83. CHAPTER IV THE THIRTEENTH CENTURY 85 Factions in Florence, 87. Frederick II crowned emperor, 90. Renewal of the Lombard League, 91. Frederick II and the Lombard League, 92. Battle of Cortenuova, 93. Pope against emperor, 94. The Guelfs expelled from Florence; battle of Fossalta, 97. Death of Frederick II: the succession, 98. The pope and the cities, 99. Florentine affairs; the Guelfs recalled, 101. Florence and Siena at war; battle of Montaperti, 102. The tyrant Ezzelino, 104. The beginning of feudal tyranny in Lombardy, 106. Perennial strife of Guelfs and Ghibellines, 108. Charles of Anjou conquers Sicily, 109. The fall of Conradin; Gregory X; Otto Visconti, 110. Ghibelline successes; the Sicilian Vespers, 112. Waning influence of king, emperor, and pope, 114. The republic of Pisa, 115. Pisa defeated by Genoa near Meloria, 116. Perfidy and fall of Ugolino, 117. Florence; the feud of the Bianchi and the Neri, 118. The pope sends Charles of Valois as conciliator, 121. CHAPTER V THE FREE CITIES AND THE EMPIRE (1300-1350 A.D.) 124