Diplomatic Revolution

The Diplomatic Revolution of 1756 was the reversal of longstanding alliances in Europe between the War of the Austrian Succession and the Seven Years' War. Austria went from an ally of Britain to an ally of France, while Prussia became an ally of Britain. The most influential diplomat involved was Prince Kaunitz of Austria.

It was part of the stately quadrille, which saw a constantly shifting pattern of alliances throughout the 18th century. It was part of efforts to preserve or upset the European balance of power.

The diplomatic change was triggered by a separation of interests between Austria, Britain, and France. The Peace of Aix-la-Chapelle, after the War of the Austrian Succession in 1748, left Austria aware of the high price it paid in having Britain as an ally. Maria Theresa of Austria had defended her claim to the Habsburg throne and had her husband, Francis Stephen, crowned Emperor in 1745. However, she had been forced to relinquish valuable territory in the process. Under British diplomatic pressure, Maria Theresa had given up most of Lombardy and occupied Bavaria. The British also forced her to cede Parma to Spain and, more importantly, to abandon the valuable state of Silesia to Prussian occupation.

During the war, Frederick II ("the Great") of Prussia had seized Silesia, one of the Bohemian crown lands. That acquisition had further advanced Prussia as a great European power, which now posed an increasing threat to Austria's German lands and to Central Europe as a whole. The growth of Prussia, dangerous to Austria, was welcomed by the British, who saw it as a means of balancing French power and reducing French influence in Germany, which might otherwise have grown in response to Austria's weakness.

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