I think Wellington saw discipline was the key to this problem. Wellington sent back Longa’s and Giron’s troops after the atrocities committed, byt the former, at Ascain. He retained Morillo’s troops but rebuked their commander for indiscipline. The remedy he suggested was to keep the troops under arms at all times. “Now I do not enter France in order to plunder: I have not had so many thousands of officers and men killed in order that the survivors should be able to rob the French. On the contrary, it is my duty and the duty of us all, to stop pillage, especially if we want to make our army live on the resources of the county”. Wellington to Morillo Wellington’s Dispatches xi, pp 288-9 and 296 cited in Oman vol vii, p219

Best wishes

Anthony