Miracle of the House of Brandenburg

The Miracle of the House of Brandenburg is the name given by Frederick II of Prussia to the failure of Russia and Austria to follow up their victory over him at the Battle of Kunersdorf on 12 August 1759 during the Seven Years' War.

After the Battle of Kunersdorf, Frederick thought Prussia faced certain defeat. He wrote that it was "a cruel reverse! I shall not survive it. I think everything is lost. Adieu pour jamais". Prussia had lost 19,000 soldiers and was left with 18,000. On 16 August he wrote that if the Russians crossed the Oder and marched on the Prussian capital, Berlin, "We'll fight them – more in order to die beneath the walls of our own city than through any hope of beating them". That day the Russian Field Marshal Saltykov and his army crossed the Oder and the day before the Austrian Field Marshal Laudon and his army had done the same. Field Marshal Daun was marching the rest of the Austrian army north from Saxony. All three forces aimed to march on Berlin.

Frederick massed 33,000 men to defend Berlin against enemy forces which he estimated totalled 90,000. However now came what Frederick called "the Miracle of the House of Brandenburg". The Austrians and the Russians proved reluctant to follow through their victory by occupying Berlin, and in September began withdrawing their forces. The Austrians and Russians had lost 20,000 men at Kunersdorf and both armies had concerns that their lines of communication were being stretched to the limit by marching so far. Also, one of Frederick's generals, his brother Prince Henry, was not involved in Kunersdorf and still posed a threat to the Austrians and Russians. Frederick regained confidence.

By December 1761, after five years of war, the strategic situation for Prussia turned bleak despite several tactical successes. As Frederick wrote on 10 December:

The Austrians are masters of Schweidnitz and the mountains, the Russians are behind the length of the Warthe from Kolberg to Posen...my every bale of hay, sack of money or batch of recruits only arriving by courtesy of the enemy or from his negligence. Austrians controlling the hills in Saxony, the Imperials the same in Thuringia, all our fortresses vulnerable in Silesia, in Pomerania, Stettin, Kustrin, even Berlin, at the mercy of the Russians.

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