In 1677 he was sent to England to solicit for Prince William the hand of Mary, daughter of James, Duke of York and future King of England. He was again in England on William's behalf in 1683 and in 1685. Later, in 1688, when William was preparing to assist in the overthrow of (now King) James including an invasion by Dutch troops, Bentinck went to some of the German princes to secure their support, or at least their neutrality. He had also been, since 1687, a medium of communication between his master and his English friends. Bentinck superintended the arrangements for the invasion, including raising money, hiring an enormous transport fleet, organising a propaganda offensive, and preparing the possible landing sites, and also sailed to England with Prince William.