On this occasion, the king's impetuosity exposed him to great danger of falling into the hands of the enemy. In order to reconnoitre the opposite bank, he crossed the river in a small boat;he had scarcely landed when he was attacked by a party of Spanish horse, from whose hands he only saved himself by a precipitate retreat.
Having at last, with the assistance of the neighbouring fishermen, succeeded in procuring a few transports, he despatched two of them across the river, bearing Count Brahe and 300 Swedes.
Scarcely had this officer time to entrench himself on the opposite bank, when he was attacked by 14 squadrons of Spanish dragoons and cuirassiers.
Superior as the enemy was in number, Count Brahe, with his small force, bravely defended himself, and gained time for the king to support him with fresh troops. The Spaniards at last retired with the loss of 600 men, some taking refuge in Oppenheim, and others in Mentz. A lion of marble on a high pillar, holding a naked sword in his paw, and a helmet on his head, was erected seventy years after the event, to point out to the traveller the spot where the immortal monarch crossed the great river of Germany.
Gustavus Adolphus now conveyed his artillery and the greater part of his troops over the river, and laid siege to Oppenheim, which, after a brave resistance, was, on the 8th December, 1631, carried by storm.
Five hundred Spaniards, who had so courageously defended the place, fell indiscriminately a sacrifice to the fury of the Swedes. The crossing of the Rhine by Gustavus struck terror into the Spaniards and Lorrainers, who had thought themselves protected by the river from the vengeance of the Swedes. Rapid flight was now their only security;every place incapable of an effectual defence was immediately abandoned.
After a long train of outrages on the defenceless citizens, the troops of Lorraine evacuated Worms, which, before their departure, they treated with wanton cruelty. The Spaniards hastened to shut themselves up in Frankenthal, where they hoped to defy the victorious arms of Gustavus Adolphus.
The king lost no time in prosecuting his designs against Mentz, into which the flower of the Spanish troops had thrown themselves.
While he advanced on the left bank of the Rhine, the Landgrave of Hesse Cassel moved forward on the other, reducing several strong places on his march.
The besieged Spaniards, though hemmed in on both sides, displayed at first a bold determination, and threw, for several days, a shower of bombs into the Swedish camp, which cost the king many of his bravest soldiers.
But notwithstanding, the Swedes continually gained ground, and had at last advanced so close to the ditch that they prepared seriously for storming the place. The courage of the besieged now began to droop.
They trembled before the furious impetuosity of the Swedish soldiers, of which Marienberg, in Wurtzburg, had afforded so fearful an example.
The same dreadful fate awaited Mentz, if taken by storm;and the enemy might even be easily tempted to revenge the carnage of Magdeburg on this rich and magnificent residence of a Roman Catholic prince.
To save the town, rather than their own lives, the Spanish garrison capitulated on the fourth day, and obtained from the magnanimity of Gustavus a safe conduct to Luxembourg; the greater part of them, however, following the example of many others, enlisted in the service of Sweden.
On the 13th December, 1631, the king made his entry into the conquered town, and fixed his quarters in the palace of the Elector. Eighty pieces of cannon fell into his hands, and the citizens were obliged to redeem their property from pillage, by a payment of 80,000 florins. The benefits of this redemption did not extend to the Jews and the clergy, who were obliged to make large and separate contributions for themselves. The library of the Elector was seized by the king as his share, and presented by him to his chancellor, Oxenstiern, who intended it for the Academy of Westerrah, but the vessel in which it was shipped to Sweden foundered at sea.
After the loss of Mentz, misfortune still pursued the Spaniards on the Rhine.
Shortly before the capture of that city, the Landgrave of Hesse Cassel had taken Falkenstein and Reifenberg, and the fortress of Koningstein surrendered to the Hessians. The Rhinegrave, Otto Louis, one of the king's generals, defeated nine Spanish squadrons who were on their march for Frankenthal, and made himself master of the most important towns upon the Rhine, from Boppart to Bacharach.
After the capture of the fortress of Braunfels, which was effected by the Count of Wetterau, with the co-operation of the Swedes, the Spaniards quickly lost every place in Wetterau, while in the Palatinate they retained few places besides Frankenthal. Landau and Kronweisenberg openly declared for the Swedes; Spires offered troops for the king's service;Manheim was gained through the prudence of the Duke Bernard of Weimar, and the negligence of its governor, who, for this misconduct, was tried before the council of war, at Heidelberg, and beheaded.
The king had protracted the campaign into the depth of winter, and the severity of the season was perhaps one cause of the advantage his soldiers gained over those of the enemy. But the exhausted troops now stood in need of the repose of winter quarters, which, after the surrender of Mentz, Gustavus assigned to them, in its neighbourhood.
