Following Frederick the Great's victory over the French at Rossbach,  George II of Great Britain, on the advice of his British ministers after the battle of Rossbach, revoked the Convention of Klosterzeven, and Hanover reentered the war. Ferdinand of Brunswick launched a winter campaign – an unusual strategy at the time – against the French occupiers. The condition of the French forces had deteriorated by this point and Richelieu began to withdraw rather than face a major battle. Shortly afterwards he resigned his post and was replaced by Louis, Count of Clermont. Clermont wrote to Louis XV describing the poor conditions of his army, which he claimed was made up of looters and casualties. Richelieu was accused of various misdemeanours including stealing the pay of his own soldiers.

Ferdinand's counterattack saw the Allied forces re-capture the port of Emden and drive the French back across the River Rhine so that by the spring Hanover had been liberated. Despite the French having been seemingly close to their goal of total victory in Europe by late 1757 – early 1758 began to reveal a shift in the overall fortunes of the war as Britain and its allies began to have more success around the globe.