In the Battle of Zusmarshausen 17 May 1648 the allies had failed to destroy the emperor’s last army and it continued to repulse probes along the Lech. Gronsfeld had learned from Tilly’s experience in 1632 and remained well back from the river, ready to pounce as the enemy crossed. Wrangel wanted to win fame by repeating Gustavus’s feat and began sending cavalry swimming across on 26 May. One of Gronsfeld’s patrols encountered them and mistakenly reported that the entire enemy army was already across. Gronsfeld retreated to Ingolstadt, exposing southern Bavaria to the enemy as in 1632–3 and 1646. The main imperial army dissolved in the retreat, falling to only 5,000 effectives, with the Bavarians numbering not many more. Gronsfeld had been shaken by Zusmarshausen and the constant alarms of the previous two weeks. This final retreat cost him Maximilian’s confidence and he was arrested along with two subordinates on 3 June and replaced by General Hunoldstein, who was followed in turn by Enkevort in August.
The elector vented his frustration on the army, and commandants of minor positions like Windsheim found themselves executed if they surrendered. More realistically, the crisis prompted him to drop his objections to Werth who was ordered to collect 6,000 imperial cavalry from Bohemia to reinforce the Bavarians. Ferdinand meanwhile entrusted imperial command to Piccolomini who had been without a position since resigning in the Netherlands in 1647. They were all competent officers, but it would take time to reorganize the demoralized army behind the river Isar. In the meantime, Maximilian joined 12,000 of his subjects and fled to Salzburg, where he had already placed his archive and treasury for safe keeping two years before.
Wrangel and Turenne invaded southern Bavaria with 24,000 men. Though Munich was spared, the rest of the area between the Lech and the Isar was plundered systematically to pressure Maximilian into another truce. Operations slowed as the generals waited for news from the peace conference. Wrangel then punched over the Isar at Freising. He reached the Inn in late June but found it swollen by heavy rain and strongly fortified by Hunoldstein. Piccolomini arrived with 3,100 Imperialists, followed by Werth and the cavalry on 3 August. Their arrival boosted morale, assisted by Piccolomini’s gesture of distributing his own salary to the unpaid troops. The Imperialists now mustered 14,000, while the Bavarians were back to 10,000 with additional militia and garrisons along the Inn and other positions across the electorate. They were on the march by 17 July.
Wrangel and Turenne retired slowly to avoid a reverse that might disrupt the final peace negotiations. Wrangel additionally wanted to deny Queen Christina an excuse to replace him as army commander. In fact, she had already named her cousin Carl Gustav of Pfalz-Zweibrücken as commander of all Sweden’s forces in the Empire on 2 June. The decision was part of her complex manoeuvres to resolve the problem of the succession without the need to marry. She recognized the difficulties she faced in persuading her subjects to accept Carl Gustav as her successor and wanted to raise his prestige by associating him with the final victory in the Empire. He had already proved himself a good subordinate under Torstensson. She now overruled objections from the Council of State and sent him with 7,150 native troops to Pomerania in late July.38
Despite having to send 2,000 men to redress the situation in Bohemia, Piccolomini continued his strategy of harrying the enemy. This placed Werth in his element. He learned that Wrangel, Turenne and a large entourage had gone hunting in the Dachau woods north of Munich on 6 October. Despite the allies posting 1,400 cavalry around the edge for security, no one noticed additional firing as Werth’s troopers attacked, until a Swedish captain collapsed, followed by the lieutenant next to him. Werth had overrun the cordon and was in the wood. The hunters became the hunted. Twenty officers disappeared in the treacherous bogs. Wrangel found himself sinking until, so he claimed, a deer sprang over the marsh showing him the way through. He escaped, but Werth took 94 prisoners and 1,000 horses. The allies burned nearby Bavarian villages in retaliation for this unsporting behaviour.
The Final Confrontation at Prague
The real action had meanwhile shifted to Bohemia. Königsmarck had set out from the Lech on 18 May through the Upper Palatinate and the Eger valley, picking up garrison troops to arrive with 3,000 men in Pilsen on 22 July. His task was to drive a rift in Austro-Bavarian relations by forcing the emperor to recall his army to protect Bohemia. Piccolomini had drained the kingdom of troops to rebuild the main army, leaving Prague weakly held. Königsmarck decided to score a coup by surprising the city that offered the last chance of a really big prize before peace prevented further plunder. He had been contacted by Ernst Ottovalsky, a Protestant lieutenant-colonel who had lost his right arm in imperial service and was disgruntled at the lack of compensation he had received.
Having given Königsmarck an address list of the rich and famous, Ottovalsky guided a party of a hundred Swedes across the battlefield of White Mountain on the night of 25 July to the western ‘Little Side’ of the city left of the Moldau. He led them to a place where the wall was being strengthened and the workmen had left a pile of earth. The Swedes used this as a ramp to get over the defences, overpower the guards and open one of the gates to Königsmarck and the main body of troops. The Swedes swiftly captured the entire Little Side, including the Hradschin, but Rodolfo Colloredo, the imperial commander, escaped by boat to the other side of the Moldau and the mayor rang the bells sounding the alarm. Prague had surrendered without a fight in 1620, 1631 and 1632, but this had taught its inhabitants what to expect from enemy occupation and they were now determined to resist. Students and citizens blocked the Charles Bridge, preventing the Swedes from entering the larger New Town east of the river.
Königsmarck let his troops loose for three days. They murdered two hundred inhabitants and plundered the vast treasures of Bohemia’s aristocracy and clergy, including Schlick’s hoard, alone worth half a million talers. Further valuable monastic libraries were shipped to Stockholm to please Christina, along with what remained of Rudolf II’s art collection. Those aristocrats unfortunate enough to be caught were held to ransom. The Swedes also threatened to hold the bones of St Norbert to ransom, until they discovered these had been removed to safety. At around 7 million tlr the loot exceeded even the haul from Bregenz.
Other Swedish detachments headed for the honey pot. Wittenberg arrived on the opposite bank with 6,000 men from Silesia on 30 July, followed by Carl Gustav and 8,000 from Saxony on 4 October. However, Puchheim and 3,500 Imperialists beat them to it, racing up the Moldau to reach Prague three days before Wittenberg. The Swedes had expected an easy success and were disheartened by the tenacious resistance from the New Town. Wittenberg temporarily drew off to ravage the countryside, giving the defenders a chance to strengthen the fortifications and drill their militia. It was not until Carl Gustav arrived that the Swedes were strong enough for a regular siege and planted batteries on the north and south-eastern sides of the New Town. Further guns fired across the Moldau from the Little Side, while infantry tried to cross the Charles Bridge protected by a movable barricade. Fighting intensified on 11 October as the besiegers tried to break in before peace was signed. Colloredo persuaded the citizens to hold out. News of the peace arrived on 5 November, but the Swedes continued their assaults for another five days until the advance guard of Piccolomini’s army finally arrived from Bavaria. The Imperialists had followed Wrangel who had also headed for Prague in October but had stopped at Nuremberg once he heard reports of the peace. Piccolomini continued his march and by 20 November the entire imperial army had withdrawn into Bohemia. Talks were already under way with Carl Gustav to demarcate the areas both sides would occupy until demobilization could be completed.