外交革命
In a realignment of traditional alliances, known as the Diplomatic Revolution of 1756, Prussia became part of a coalition led by Britain, which also included long-time Prussian competitor Hanover. At the same time, Austria ended centuries of conflict by allying with France, along with Saxony, Sweden and Russia. Spain aligned formally with France in 1762. Spain unsuccessfully attempted to invade Britain's ally Portugal, attacking with their forces facing British troops in Iberia. Smaller German states either joined the Seven Years' War or supplied mercenaries to the parties involved in the conflict.