Mary, daughter of Duke of Brunswick, | _d._ 1191. +-----+-------------+ Henry IV. of and ancestor of FREDERICK II., | | Brabant. later dukes. _m._ 1. Constance of Aragon. Beatrice, Beatrice, 2. Iolande of Brienne. _m._ Otto IV. _m._ Ferdinand III. 3. Isabella, daughter of of Castile. John of England. | (1) (2) (3) (3)| Alfonso X. +--------------------+----------------+--------------+--------------+-------------------+ of Castile | | | | | | Henry, CONRAD IV. Henry, Margaret, Enzio, Manfred, _d._ 1242. 1250–1254. _d._ 1253. _m._ Albert of _d._ 1272 _d._ 1266 | Thuringia. (illegitimate). (illegitimate). Conradin, | _d._ 1268. Constance, _m._ Peter III. of Aragon. CHAPTER XI FREDERICK BARBAROSSA AND ALEXANDER III. THE RENEWED CONFLICT OF PAPACY AND EMPIRE (1152–1190).[18] Election and Policy of Frederick I.—Frederick and Adrian IV.—Fall of Arnold of Brescia—Frederick’s early German Policy—The Burgundian Marriage and the Diet of Besançon—Breach with the Papacy—Frederick’s Second Italian Journey—Diet of Roncaglia and Destruction of Milan—Alexander III. and the Antipopes—The Lombard League—Battle of Legnano—Peace of Constance—Frederick and Germany—Fall of Henry the Lion—Division of the Saxon Duchy—Union of Sicily with the Empire—The Lateran Council and the last days of Alexander III.—His Successors—Urban III. and Frederick—The Crusade and Death of Frederick—His Personality and Character. [Sidenote: Election of Frederick I., 1152.]