Banner and Torstensohn, had, in 1646, been appointed Commander-in-chief
of the Swedish army, which, besides Koenigsmark's flying corps and the
numerous garrisons disposed throughout the empire, amounted to about
8,000 horse, and 15,000 foot. The Archduke, after reinforcing his army,
which already amounted to 24,000 men, with twelve Bavarian regiments of
cavalry, and eighteen regiments of infantry, moved against Wrangel, in
the hope of being able to overwhelm him by his superior force before
Koenigsmark could join him, or the French effect a diversion in his
favour. Wrangel, however, did not await him, but hastened through Upper
Saxony to the Weser, where he took Hoester and Paderborn. From thence
he marched into Hesse, in order to join Turenne, and at his camp at
Wetzlar, was joined by the flying corps of Koenigsmark. But Turenne,
fettered by the instructions of Mazarin, who had seen with jealousy the
warlike prowess and increasing power of the Swedes, excused himself on
the plea of a pressing necessity to defend the frontier of France on the
side of the Netherlands, in consequence of the Flemings having failed to
make the promised diversion. But as Wrangel continued to press his just
demand, and a longer opposition might have excited distrust on the part
of the Swedes, or induce them to conclude a private treaty with Austria,
Turenne at last obtained the wished for permission to join the Swedish
army.

The junction took place at Giessen, and they now felt themselves strong
enough to meet the enemy. The latter had followed the Swedes into
Hesse, in order to intercept their commissariat, and to prevent their
union with Turenne. In both designs they had been unsuccessful; and the
Imperialists now saw themselves cut off from the Maine, and exposed to
great scarcity and want from the loss of their magazines. Wrangel took
advantage of their weakness, to execute a plan by which he hoped to give
a new turn to the war. He, too, had adopted the maxim of his