war called the War of Spanish Succession, in which Marlborough and Eugene were the heroes, was waged with Louis XIV. to prevent the union of France and Spain, as seemed probable when the bequest of the Spanish throne was made to the Duc d’Anjou, grandson of Louis XIV., who had married a Spanish princess.  The victories of Marlborough and Eugene prevented this union of the two most powerful monarchies of Europe at that time, and the treaty of Utrecht permanently guarded against it.  The title of the Duc d’Anjou to the Spanish throne was recognized, but only on the condition that he renounced for himself and his descendants all claim to the French crown,—­while the French monarch renounced on his part for his descendants all claim to the Spanish throne, which was to descend, against ancient usages, to the male heirs alone.  The Spanish Cortes and the Parliament of Paris ratified this treaty, and it became incorporated with the public law of Europe.

Up to this time the relations between England and France had been most friendly.  Louis Philippe had visited Queen Victoria at Windsor, and the Queen of England had returned the visit to the French king with great pomp at his chateau d’Eu, in Normandy, where magnificent fetes followed.  Guizot and Lord Aberdeen, the English foreign minister, were also in accord, both statesmen adopting a peace policy.  This entente cordiale between England and France had greatly strengthened the throne of Louis Philippe, who thus had the moral support of England.

But this moral support was withdrawn when the king, in 1846, yielding to ambition and dynastic interests, violated in substance the treaty of Utrecht by marrying his son, the Duc de Montpensier, to the Infanta, daughter of Christina the Queen of Spain, and second wife of Ferdinand VII., the last of the Bourbon kings of Spain.  Ferdinand left two daughters by Queen Christina, but no son.  By the Salic law his younger brother Don Carlos was the legitimate heir to the throne; but his ambitious wife, who controlled him, influenced him to alter the law of succession, by which his eldest daughter became the heir.  This bred a civil war; but as Don Carlos was a bigot and tyrant, like all his family, the liberal party in France and England brought all their influence to secure the acknowledgment of the claims of Isabella, now queen, under the regency of her mother Christina.  But her younger sister, the Infanta, was also a great matrimonial prize, since on the failure of issue in case the young queen married, the Infanta would be the heir to the crown.  By the intrigues of Louis Philippe, aided by his astute, able, but subservient minister Guizot, it was contrived to marry the young queen to the Duke of Cadiz, one of the degenerate descendants of Philip V., since no issue from the marriage was expected, in which case the heir of the Infanta Donna Fernanda, married to the Duc de Montpensier, would some day ascend the throne of Spain.  The English government, especially