A combined Danish-German force led by Christian IV of Denmark was defeated by Johan Tzerclaes, Count of Tilly, commanding an army of the Catholic League loyal to Emperor Ferdinand II.

[4] In May 1625, Christian was appointed commander of the Upper and Lower Circle forces; these numbered less than 7,000 ill-trained militia, most of whom were only fit for garrison duty, and recruiting professional troops required subsidies from England and the Dutch Republic.

[9] Since relieving these garrisons had been a primary objective for Christian, he decided to cut his losses and withdraw, but the poor roads impeded the movement of the baggage train and guns and slowed his retreat.

[10] For three successive days, the rearguard fought off attacks by Tilly's cavalry until on 27 August Christian decided to make a stand at Lutter am Barenberge, twenty miles from Wolfenbüttel.

His position appeared extremely strong; although the Neile and Hummecke rivers immediately in front had largely dried out, woods on either side protected both flanks, while their artillery covered the only bridge.

[13] Fuchs' infantry lost formation crossing the river, while Tilly ordered his artillery to hold their fire until they were only 100 metres away; the impact of this devastating volley shattered the attack and the Danes fell back to their original positions in total confusion.

[3] Unable to hold Wolfenbüttel, Christian established winter quarters further north at Stade, but he was abandoned by the majority of his German allies, who had little interest in replacing Imperial domination for Danish.

[11] Defeat at Lutter left Mansfeld stranded in the Tatra Mountains, his army mutinous, unpaid and starving, while his ally Gabriel Bethlen opened peace negotiations with Ferdinand.