The battle of Müchengrätz (28 June 1866) was a missed chance for the Prussians to isolate and destroy the western part of the Austrian army on the River Iser (Austro-Prussian War).
At the start of the war the Prussians invaded Bohemia in three armies. The 2nd Army, under the Crown Prince, made up the left wing of the attack, and ended up facing the main Austrian army. The Army of the Elbe, on the Prussian right, occupied Saxony before advancing to the Saxon border, and the 1st Army (Prince Frederick Charles) advanced across the eastern tip of Saxony into Bohemia. These last two armies were meant to operate together, and Prince Frederick Charles was given overall command of them.
The Austrians had two corps on the Iser. The first was the Austrian I Corps, commanded by Clam-Gallas. The second was the Saxon Corps, under Crown Prince Albert of Saxony. On 24 June the Crown Prince was placed in overall command, but he deferred to Clam-Gallas on some key decisions, including the decision not to defend Turnau on the Iser, north-east of their main concentration area.
The Austrians suffered from indecision at the highest levels. General Benedek, the supreme Austrian commander in Bohemia, originally intended to concentrate on the Iser and attack the right wing of the Prussia attack. This required the forces already on that river to defend it against the Prussians, and orders to hold the Iser and in particular Müchengrätz and Turnau, were despatched on 26 June.
By the time these orders arrived the Austrians had already fought two minor actions, and lost control of part of the Iser. To the north-west of Müchengrätz Leiningen's Brigade had suffered a defeat at Hühnerwasser. More importantly the Austrian outposts at Liebenau had been defeated by the Prussian 8th Division from the 1st Army. The Austrians had retreated across the Iser and abandoned Turnau, which the Prussians promptly occupied.
When Benedek's orders arrived Clam-Gallas and the Crown Prince decided to try and restore the situation by recapturing Turnau. Their attack never got anywhere near its target. Instead they ran into the Prussians around the village of Podol (on the west bank of the Iser), and suffered another defeat. The defeated Austrians pulled back to Müchengratz.
For once 27 June saw the Austrians and Saxons react to events quicker than the Prussians. Early in the day Crown Prince Albert received a telegram that informed him that the main Austrian army was still at Josephstadt, and hoped to reach Gitschin, half way to the Iser, by 30 June. The Prince realised that if he didn't abandon the Iser the Prussians could overwhelm his army, and he ordered his troops to prepare for a retreat to Gitschin on 28 June.
On the Prussian side Prince Frederick Charles missed the change to trap the Austrians and Saxons on the Iser, and instead spent the day consolidating his existing positions and preparing for a complex assault, also to be carried out on 28 June. The Army of the Elbe was to advance from Niemes and attack the Austrian position from the west at 9am. The 1st Army would then attack the Austrians in the flank and rear. General Tümpling's 5th Division was sent east towards Gitschin.
This provides an example of the peril of using 'left' and 'right' to describe an army's layout - for the Prussians, expected the Austrians to stand and fight, the Austrian front would be facing west, and the Austrian right flank would be facing north. To the Austrians, retreating to the east, their front was facing east, and their left flank facing north).
The Austrian plan for the 28th was for one brigade to occupy Podkost (about half way between Münchengrätz and Gitschin, north of the main road), a position that could protect the northern flank of the retreat. The retreat was to be led by a cavalry division which was to set off at 4am to check the road to Gitschin. The main army was to move off at 5am, leaving Leiningen's brigade to act as a rearguard. Much of this force was posted at Kloster, on the west/ north bank of the Iser, opposite Münchengrätz. The Austrians also posted an artillery force on the Muskey Berg, a sizable hill east of the town that made a good defensive position.
The Army of the Elbe attacked as ordered. Its first task was to clear the Austrians out of Kloster. The Army attacked in two columns - the right-hand column was to attack the village, while the left-hand column (14th Division) was to cross the Iser further upstream and get behind a potentially strong Austrian position on another hill west of the Muskey Berg.
Once the fighting began, two divisions from the 1st Army began to move south to hit the Austrians in the rear (Horn and Fransecky). At first it looked as if Kloster would be difficult to capture, but the Austrians retreated once the Prussians began to outflank their position. At the same time the Prussian 14th Division crossed the river a little upstream. Both Prussian forces then headed for Münchengrätz, with the 14th Division arriving first.
The two divisions from the Army of the Elbe struggled to approach the Muskey Berg. An attempt was put in place to use cavalry to outflank the defenders, but this wasn't needed. By around noon the Prussian 7th Division (Fransecky) was approaching from the north-east, and the Austrians withdrew. The fighting was over by 1pm, with the Prussians in command of the town, but with most of the Austrians and Saxons safely away.
There was also fighting at Podkost. Ringelsheim's brigade arrived on the evening of 27th and prepared to defend the village and nearby castle. The first Prussian attack came at around 11pm, and lasted until 1am. The Austrian outposts were pushed in, but they held on to their main position. The Prussians attacked again at 3am, but were repulsed. At around 7am the Austrians began to retreat east towards Gitschin, having successfully protected the northern flank of the retreat.
As often happened during this war the Austrians suffered heavier losses than the Prussians. In this case the Prussians lost 8 officers and 333 men (46 killed, the rest wounded or missing). The Austrians lost at least 20 officers and 1,634 men, including 5 officers and 1,211 men taken prisoner.
The day ended with the I Austrian Corps half way to Gitschin and the Saxon Corps a short distance to its south-west. On the Prussian side the Army of the Elbe occupied Münchengrätz, while part of the 1st Army advanced east towards Gitschin. The Prussians did suffer from one problem in the aftermath of the battle. Prince Frederick Charles had concentrated both of his armies on the intended battlefield, but he now had around 100,000 men in a very small area, and it proved to be difficult to get supplies to the troops.
On the following day the Prussians attacked the Austrians in their new position at Gitschin (29 June 1866). This time the Austrians fought well, but they were pushed back during the day, and then forced to retreat by news from Benedek's HQ. The main Austrian army had suffered a series of defeats of its own east of the Elbe, and the plan to unit at Gitschin had been abandoned. Clam Gallas and the Crown Prince had to continue their retreat east to find the main army, although Clam Gallas would be removed from command soon after reaching it.