Richelieu desired nothing so much as to diminish the influence of the Swedes in the German war, and to obtain the direction of it for himself. To secure this end, nothing appeared more effectual than to detach from the Swedes their bravest general, to win him to the interests of France, and to secure for the execution of its projects the services of his arm.
From a prince like Bernard, who could not maintain himself without foreign support, France had nothing to fear, since no success, however brilliant, could render him independent of that crown.
Bernard himself came into France, and in October, 1635, concluded a treaty at St. Germaine en Laye, not as a Swedish general, but in his own name, by which it was stipulated that he should receive for himself a yearly pension of one million five hundred thousand livres, and four millions for the support of his army, which he was to command under the orders of the French king. To inflame his zeal, and to accelerate the conquest of Alsace, France did not hesitate, by a secret article, to promise him that province for his services; a promise which Richelieu had little intention of performing, and which the duke also estimated at its real worth. But Bernard confided in his good fortune, and in his arms, and met artifice with dissimulation. If he could once succeed in wresting Alsace from the enemy, he did not despair of being able, in case of need, to maintain it also against a friend. He now raised an army at the expense of France, which he commanded nominally under the orders of that power, but in reality without any limitation whatever, and without having wholly abandoned his engagements with Sweden.
He began his operations upon the Rhine, where another French army, under Cardinal Lavalette, had already, in 1635, commenced hostilities against the Emperor.
Against this force, the main body of the Imperialists, after the great victory of Nordlingen, and the reduction of Swabia and Franconia had advanced under the command of Gallas, had driven them as far as Metz, cleared the Rhine, and took from the Swedes the towns of Metz and Frankenthal, of which they were in possession. But frustrated by the vigorous resistance of the French, in his main object, of taking up his winter quarters in France, he led back his exhausted troops into Alsace and Swabia.
At the opening of the next campaign, he passed the Rhine at Breysach, and prepared to carry the war into the interior of France.
He actually entered Burgundy, while the Spaniards from the Netherlands made progress in Picardy; and John De Werth, a formidable general of the League, and a celebrated partisan, pushed his march into Champagne, and spread consternation even to the gates of Paris.
But an insignificant fortress in Franche Comte completely checked the Imperialists, and they were obliged, a second time, to abandon their enterprise.
The activity of Duke Bernard had hitherto been impeded by his dependence on a French general, more suited to the priestly robe, than to the baton of command; and although, in conjunction with him, he conquered Alsace Saverne, he found himself unable, in the years 1636 and 1637, to maintain his position upon the Rhine. The ill success of the French arms in the Netherlands had cheated the activity of operations in Alsace and Breisgau; but in 1638, the war in that quarter took a more brilliant turn. Relieved from his former restraint, and with unlimited command of his troops, Duke Bernard, in the beginning of February, left his winter quarters in the bishopric of Basle, and unexpectedly appeared upon the Rhine, where, at this rude season of the year, an attack was little anticipated.
The forest towns of Laufenburg, Waldshut, and Seckingen, were surprised, and Rhinefeldt besieged. The Duke of Savelli, the Imperial general who commanded in that quarter, hastened by forced marches to the relief of this important place, succeeded in raising the siege, and compelled the Duke of Weimar, with great loss to retire.
But, contrary to all human expectation, he appeared on the third day after, (21st February, 1638,) before the Imperialists, in order of battle, and defeated them in a bloody engagement, in which the four Imperial generals, Savelli, John De Werth, Enkeford, and Sperreuter, with 2000 men, were taken prisoners. Two of these, De Werth and Enkeford, were afterwards sent by Richelieu's orders into France, in order to flatter the vanity of the French by the sight of such distinguished prisoners, and by the pomp of military trophies, to withdraw the attention of the populace from the public distress.
The captured standards and colours were, with the same view, carried in solemn procession to the church of Notre Dame, thrice exhibited before the altar, and committed to sacred custody.
The taking of Rhinefeldt, Roeteln, and Fribourg, was the immediate consequence of the duke's victory. His army now increased by considerable recruits, and his projects expanded in proportion as fortune favoured him.
The fortress of Breysach upon the Rhine was looked upon as holding the command of that river, and as the key of Alsace. No place in this quarter was of more importance to the Emperor, and upon none had more care been bestowed.
To protect Breysach, was the principal destination of the Italian army, under the Duke of Feria; the strength of its works, and its natural defences, bade defiance to assault, while the Imperial generals who commanded in that quarter had orders to retain it at any cost. But the duke, trusting to his good fortune, resolved to attempt the siege.
Its strength rendered it impregnable; it could, therefore, only be starved into a surrender; and this was facilitated by the carelessness of the commandant, who, expecting no attack, had been selling off his stores.
