By late July, Cumberland believed his army was ready for battle and adopted a defensive position around the village of Hastenbeck. The French won a narrow victory over him there, but as Cumberland retreated his force began to disintegrate as morale collapsed. Despite his victory, d'Estrées was shortly afterwards replaced as commander of the French army by the Duc de Richelieu, who had recently distinguished himself leading the French forces that had captured Minorca. Richelieu's orders followed the original strategy of taking total control of Hanover, and then turning west to offer assistance to the Austrians attacking Prussia.

Cumberland's forces continued to withdraw northwards. The French pursuit was slowed by further problems with supplies, but they continued to steadily pursue the retreating Army of Observation. In an effort to cause a diversion and provide some relief to Cumberland, the British planned an expedition to raid the French coastal town of Rochefort – hoping that the sudden threat would compel the French to withdraw troops from Germany to protect the French coast against further attacks. Under Richelieu the French continued their drive, taking Minden and then capturing the city of Hanover on 11 August.