Mars and Hercules are appropriate figures from mythology to select for the Duke of Marlborough: they represent war and strength. The central panel shows Marlborough's arms including the Order of the Garter he had been awarded by Queen Anne in 1702, which riband he wears throughout Laguerre's murals at Marlborough House. This token of royal approval was much prized by the Duke and Duchess, although its presence in the house must have taken on an ambivalent quality on the wall after the couple's fall from grace in 1710-11.

These grisaille panels show signs of substantial overpainting and it is possible that very little remains that is original.