The Invasion of Hanover took place in 1757 during the Seven Years' War when a French army under Louis Charles César Le Tellier, duc d'Estrées advanced into the Electorate of Hanover and neighbouring German states, following the Battle of Hastenbeck. French forces overran most of Hanover. This action forced the Hanoverian Army of Observation, intended to defend the Electorate, to Stade on the North Sea coast. At the Convention of Klosterzeven the Duke of Cumberland agreed to disband his army and acknowledge the French occupation of the Electorate.

The Seven Years' War (1756–1763) was a global conflict involving most of the European great powers, fought primarily in Europe and the Americas. One of the opposing alliances was led by Great Britain and Prussia. The other alliance was led by France, backed by Spain, Saxony, Sweden, and Russia. Related conflicts include the 1754 to 1763 French and Indian War, and 1762 to 1763 Anglo-Spanish War.