Guébriant's Franco-Weimarian Army of Germany consisted of 2,000 infantry in 12 regiments and 3,500 cavalry in another 12 regiments. It joined up with Eberstein's Hessian army of 4,000 men, split in equal halves of infantry and cavalry, in December 1641 near the Rhine. The Allies crossed the Rhine at Wesel and began to ravage the vicinity of Cologne. Lamboy, whose Imperial force of 9,000 men and 6 guns had been assisting the Spanish in the Low Countries, crossed the Meuse as Imperial Field Marshal Melchior Graf von Hatzfeldt marched from winter quarters in Würzburg with 7,000 reinforcements. Guébriant resolved to attack Lamboy before Hatzfeldt could arrive. The Allies were also running out of food. A third of Lamboy's men were combat ineffective due to sickness or lack of weapons. Overconfident, he ignored his instructions to wait for Hatzfeldt and set up a strong position behind a double ditch near Hüls.