In an unsuccessful enterprise in Flanders, Count Henry Casimir of Nassau was mortally wounded, adding another to the list of those of that illustrious family whose lives were lost in the service of their country.  His brother, Count William Frederick, succeeded him in his office of stadtholder of Friesland; but the same dignity in the provinces of Groningen and Drent devolved on the Prince of Orange.  The latter had conceived the desire of a royal alliance for his son William.  Charles I. readily assented to the proposal of the states-general that this young prince should receive the hand of his daughter Mary.  Embassies were exchanged; the conditions of the contract agreed on; but it was not till two years later that Van Tromp, with an escort of twenty ships, conducted the princess, then twelve years old, to the country of her future husband.  The republic did not view with an eye quite favorable this advancing aggrandizement of the House of Orange.  Frederick Henry had shortly before been dignified by the king of France, at the suggestion of Richelieu, with the title of “highness,” instead of the inferior one of “excellency”; and the states-general, jealous of this distinction granted to their chief magistrate, adopted for themselves the sounding appellation of “high and mighty lords.”  The Prince of Orange, whatever might have been his private views of ambition, had however the prudence to silence all suspicion, by the mild and moderate use which he made of the power, which he might perhaps have wished to increase, but never attempted to abuse.

On the 9th of November, 1641, the prince-cardinal Ferdinand died at Brussels in his thirty-third year; another instance of those who were cut off, in the very vigor of manhood, from worldly dignities and the exercise of the painful and inauspicious duties of governor-general of the Netherlands.  Don Francisco de Mello, a nobleman of highly reputed talents, was the next who obtained this onerous situation.  He commenced his governorship by a succession of military operations, by which, like most of his predecessors, he is alone distinguished.  Acts of civil administration are scarcely noticed by the historians of these men.  Not one of them, with the exception of the archduke Albert, seems to have valued the internal interests of the government; and he alone, perhaps, because they were declared and secured as his own.  De Mello, after taking some towns, and defeating the marshal De Guiche in the battle of Hannecourt, tarnished all his fame by the great faults which he committed in the famous battle of Rocroy.  The duke of Enghien, then twenty-one years of age, and subsequently so celebrated as the great Conde, completely defeated De Mello, and nearly annihilated the Spanish and Walloon infantry.  The military operations of the Dutch army were this year only remarkable by the gallant conduct of Prince William, son of the Prince of Orange, who, not yet seventeen years of age, defeated, near Hulst, under the eyes of his father, a Spanish detachment in a very warm skirmish.