This was a British pair of deception operations designed to persuade the Germans and Italians holding the 'Braun' (ii) lodgement in northern Tunisia that the final Allied assaults would be delivered in areas other than those in which they were actually to be made (April 1943).
Designed to supporting the final assault on Tunis of General the Hon. Sir Harold Alexander’s 18th Army Group, to be made by Lieutenant General K. A. N. Anderson’s Allied 1st Army and Lieutenant General George S. Patton’s US Corps attacking from the west.
The 'story' promulgated by 'Cowper' was that this offensive would in fact be undertaken by General Sir Bernard Montgomery’s British 8th Army from the south, and was passed to the Axis powers by a fictitious French airman in Algiers and by the 'Cheese' double agent channel. The deception was given verisimilitude, after the redeployment of a British armoured division from the 8th Army to the 1st Army, by this formation’s replacement in the south by dummy equipment and the use of a radio deception in the north to suggest that the British division was in fact Major General Orlando Ward’s US 1st Armored Division.
A variant of the basic plan was 'Cowper II', which covered a revival of the offensive after a German counterattack.
'Cowper' was the last tactical deception in North Africa as Tunis fell to the Allies on 7 May.