In the years immediately after the War of the Austrian Succession, a ‘diplomatic revolution’ took place in Europe. France and Austria, with support from Russia, Sweden, and Saxony, aligned themselves against Frederick II of Prussia. In 1756 Frederick made a pre‐emptive strike into Saxony, followed a year later by an advance into Bohemia. As his enemies responded by threatening Prussia from all sides, Frederick turned to Britain for aid. An ‘Army of Observation’ under the duke of Cumberland was deployed to western Germany, but when the French invaded, Cumberland was beaten at Hastenbeck (26 July 1757) and forced to sign a convention to disband his army. This was countermanded by the British prime minister, William Pitt (the Elder), who sent British units to reinforce the remains of Cumberland's army, under the command of Ferdinand of Brunswick. A hard‐won victory at Minden on 1 August 1759 allowed the ‘Army of Execution’ to consolidate its hold over western Germany, but the war was by no means over. Further east, Frederick had managed to survive only by fighting desperate and costly battles at Zorndorf (1758) and Kunersdorf (1759); he had to fight further battles at Liegnitz and Torgau (1760) and at Schweidnitz (1762), to defeat the French, Austrians, and Russians in turn. Only when Russia withdrew from the war on the death of the Tsarina Elizabeth in 1762 did Frederick receive any respite. The war ended in February 1763 with the peace of Paris.
But the fighting was not confined to Europe. In 1758 Pitt dispatched an expeditionary force of 12,000 men under General Amherst to capture the fortress of Louisbourg and, when this proved successful, ordered a much more ambitious advance into French‐held Canada. On the night of 12–13 September 1759 Major‐General James Wolfe, commanding no more than 3,000 men, mounted a surprise attack on Quebec. The ensuing battle was short and decisive; although both Wolfe and his opponent Montcalm were fatally wounded, the French retreated and Quebec fell. Montreal followed, leaving Britain in control of much of Canada.
By then, the British had also consolidated their power in India, where the pro‐French nawab Siraj‐ud‐Daula was defeated by Robert Clive at the battle of Plassey in 1757 to give the East India Company control of Bengal. By 1761, when the French outpost at Pondicherry surrendered to General Eyre Coote, this control had been extended into the Carnatic.