But in this expectation he was disappointed; for the king, instead of advancing to meet him at Weissenfels, made preparations for intrenching himself near Naumburg, with the intention of awaiting there the reinforcements which the Duke of Luneburg was bringing up.  Undecided whether to advance against the king through the narrow passes between Weissenfels and Naumburg or to remain inactive in his camp, he called a council of war, in order to have the opinion of his most experienced generals.  None of these thought it prudent to attack the king in his advantageous position.  On the other hand, the preparations which the latter made to fortify his camp plainly showed that it was not his intention soon to abandon it.  But the approach of winter rendered it impossible to prolong the campaign and by a continued encampment to exhaust the strength of the army, already so much in need of repose.  All voices were in favor of immediately terminating the campaign, and the more so, as the important city of Cologne upon the Rhine was threatened by the Dutch, while the progress of the enemy in Westphalia and the Lower Rhine called for effective reinforcements in that quarter.  Wallenstein yielded to the weight of these arguments, and, almost convinced that, at this season, he had no reason to apprehend an attack from the King, he put his troops into winter-quarters, but so that, if necessary, they might be rapidly assembled.  Count Pappenheim was dispatched, with a great part of the army, to the assistance of Cologne, with orders to take possession, on his march, of the fortress of Moritzburg, in the territory of Halle.  Different corps took up their winter-quarters in the neighboring towns, to watch, on all sides, the motions of the enemy.  Count Colloredo guarded the castle of Weissenfels, and Wallenstein himself encamped with the remainder not far from Merseburg, between Flotzgaben and the Saal, from whence he purposed to march to Leipzic and to cut off the communication between the Saxons and the Swedish army.

Scarcely had Gustavus Adolphus been informed of Pappenheim’s departure, when, suddenly breaking up his camp at Naumburg, he hastened with his whole force to attack the enemy, now weakened to one half.  He advanced, by rapid marches, toward Weissenfels, from whence the news of his arrival quickly reached the enemy and greatly astonished the Duke of Friedland.  But a speedy resolution was now necessary; and the measures of Wallenstein were soon taken.  Though he had little more than 12,000 men to oppose to the 20,000 of the enemy, he might hope to maintain his ground until the return of Pappenheim, who could not have advanced farther than Halle, five miles distant.  Messengers were hastily dispatched to recall him, while Wallenstein moved forward into the wide plain between the Canal and Luetzen, where lie awaited the King in full order of battle, and, by this position, cut off his communication with Leipzic and the Saxons auxiliaries.