On the 4th August Maurice broke up his camp in Flanders, and leaving five thousand men under Colonel Van der Noot, to guard the positions there, advanced rapidly to Deventer, with the intention of saving Lingen.  It was too late.  That very important place had been culpably neglected.  The garrison consisted of but one cannoneer, and he had but one arm.  A burgher guard, numbering about three hundred, made such resistance as they could, and the one-armed warrior fired a shot or two from a rusty old demi-cannon.  Such opposition to the accomplished Italian was naturally not very effective.  On the 18th August the place capitulated.  Maurice, arriving at Deventer, and being now strengthened by his cousin Lewis William with such garrison troops as could be collected, learned the mortifying news with sentiments almost akin to despair.  It was now to be a race for Coeworden, and the fleet-footed Spinola was a day’s march at least in advance of his competitor.  The key to the fatal morass would soon be in his hands.  To the inexpressible joy of the stadholder, the Genoese seemed suddenly struck with blindness.  The prize was almost in his hands and he threw away all his advantages.  Instead of darting at once upon Coeworden he paused for nearly a month, during which period he seemed intoxicated with a success so rapidly achieved, and especially with his adroitness in outwitting the great stadholder.  On the 14th September he made a retrograde movement towards the Rhine, leaving two thousand five hundred men in Lingen.  Maurice, giving profound thanks to God for his enemy’s infatuation, passed by Lingen, and having now, with his cousin’s reinforcements, a force of nine thousand foot and three thousand horse, threw himself into Coeworden, strengthened and garrisoned that vital fortress which Spinola would perhaps have taken as easily as he had done Lingen, made all the neighbouring positions secure, and then fell back towards Wesel on the Rhine, in order to watch his antagonist.  Spinola had established his headquarters at Ruhrort, a place where the river Ruhr empties into the Rhine.  He had yielded to the remonstrances of the Archbishop of Cologne, to whom Kaiserwerth belonged, and had abandoned the forts which Bucquoy, under his directions, had constructed at that place.

The two armies now gazed at each other, at a respectful distance, for a fortnight longer, neither commander apparently having any very definite purpose.  At last, Maurice having well reconnoitred his enemy, perceived a weak point in his extended lines.  A considerable force of Italian cavalry, with some infantry, was stationed at the village of Mulheim, on the Ruhr, and apparently out of convenient supporting distance from Spinola’s main army.  The stadholder determined to deliver a sudden blow upon this tender spot, break through the lines, and bring on a general action by surprise.  Assembling his well-seasoned and veteran troopers in force, he divided them into two formidable bands, one under the charge of his young brother Frederic Henry, the other under that most brilliant of cavalry officers, Marcellus Bax, hero of Turnhout and many another well-fought field.