Appointed a Knight of the Order of the Garter in December 1710, Campbell was promoted to full general and given command of all British forces in Spain at the instigation of the Harley Ministry in January 1711. He replaced James Stanhope who had been forced to surrender at Brihuega the previous December. The Harley government was negotiating an agreement with France which would see Britain recognise Philip V of Spain, in exchange for being allowed to retain Gibraltar and Minorca.