The plan of these combined measures was soon acted on. The French army took the field under the command of the marshals De Chatillon and De Breeze; and defeated the Spaniards in a bloody battle, near Avein, in the province of Luxemburg, on the 20th of May, 1635, with the loss of four thousand men. The victors soon made a junction with the Prince of Orange; and the towns of Tirlemont, St. Trond, and some others, were quickly reduced. The former of these places was taken by assault, and pillaged with circumstances of cruelty that recall the horrors of the early transactions of the war. The Prince of Orange was forced to punish severely the authors of these offences. The consequences of this event were highly injurious to the allies. A spirit of fierce resistance was excited throughout the invaded provinces. Louvain set the first example. The citizens and students took arms for its defence; and the combined forces of France and Holland were repulsed, and forced by want of supplies to abandon the siege, and rapidly retreat. The prince-cardinal, as Ferdinand was called, took advantage of this reverse to press the retiring French; recovered several towns; and gained all the advantages as well as glory of the campaign. The remains of the French army, reduced by continual combats, and still more by sickness, finally embarked at Rotterdam, to return to France in the ensuing spring, a sad contrast to its brilliant appearance at the commencement of the campaign. The military events for several ensuing years present nothing of sufficient interest to induce us to record them in detail. A perpetual succession of sieges and skirmishes afford a monotonous picture of isolated courage and skill; but we see none of those great conflicts which bring out the genius of opposing generals, and show war in its grand results, as the decisive means of enslaving or emancipating mankind. The prince-cardinal, one of the many who on this bloody theatre displayed consummate military talents, incessantly employed himself in incursions into the bordering provinces of France, ravaged Picardy, and filled Paris with fear and trembling. He, however, reaped no new laurels when he came into contact with Frederick Henry, who, on almost every occasion, particularly that of the siege of Breda, in 1637, carried his object in spite of all opposition. The triumphs of war were balanced; but Spain and the Belgian provinces, so long upheld by the talent of the governor-general, were gradually become exhausted. The revolution in Portugal, and the succession of the duke of Braganza, under the title of John IV., to the throne of his ancestors, struck a fatal blow to the power of Spain. A strict alliance was concluded between the new monarch of France and Holland; and hostilities against the common enemy were on all sides vigorously continued.