 In 1757, the war having spread to the continent, Cumberland was placed at the head of the Hanoverian Army of Observation, intended to defend Hanover (of which George II was Elector) from a French invasion.At the Battle of Hastenbeck, near Hamelin, on 26 July 1757, Cumberland's army was defeated by the superior forces of d'Estrées.Despite seemingly having the advantage towards the end of the battle, Cumberland's forces began to retreat.