The agreement was deeply unpopular with Hanover's ally Prussia, whose western frontier was severely weakened by the agreement. After the Prussian victory at Rossbach on 5 November 1757, King George II was encouraged to disavow the treaty. Under pressure from Frederick the Great and William Pitt, the convention was subsequently revoked and Hanover re-entered the war the following year. The Duke of Cumberland who had signed the agreement on behalf of Hanover was disgraced when he returned to Britain, ending his previously distinguished military career. He was replaced as commander by Duke Ferdinand of Brunswick.