'Cascade' was a British deception plan based on the creation of a false order of battle, designed to keep the Axis forces guessing as to the strength of the Allies in the Mediterranean theatre, by the use of bogus troop formations, radio traffic and double agents (1941/42).

The British forces in the Middle East were notably weak during 1941 and into the early part of 1942, and in an effort to deter any major Axis offensive they planned a deception operation. This was begun by 'A' Force under Colonel Dudley W. Clarke in 1941, and in 1942 matured into 'Cascade'. The undertaking’s object was the creation of a false but convincingly potent order of battle to keep the Axis leadership in the Mediterranean theatre from correctly estimating the strength of the Allies in the theatre.

The undertaking was based on the use of bogus troop formations, radio traffic misinformation, and double agents. In 1941 'A' Force, which was the British organisation responsible for army intelligence operations in the Middle East, had already created three bogus formations in the form of the 1^st SAS Brigade, the 10^th Armoured Division in the Western Desert, and the 7^th Division to garrison Cyprus. This fabrication was then enlarged systematically into a plan that would inflate the supposed British strength throughout the Middle East.

In March 1942 the actual British strength stood at five armoured and 10 infantry divisions, and 'Cascade' was intended to boost this strength to a supposed eight armoured and 21 infantry divisions in a fashion that would become apparent to the Axis intelligence apparatus. The plan demanded the creation of bogus units to be shipped from bases in the UK, Australia, New Zealand, India and South Africa. An order of battle had to be drawn up for these units, crests and signs had to be created, and some form of physical presence was needed to convince Axis agents that the formations actually existed.

False radio traffic, and information gathered by civilian informers in Egypt, increased the Axis impression that these units were both real and present in the theatre. Most of the civilian agents, however, were double agents controlled by 'A' Force through a double-agent network called 'Cheese'.

Axis documents, captured during and after the 2^nd Battle of El Alamein, revealed that 'Cascade' had been successful. An analysis by 'A' Force, delivered on 19 November 1942, showed that Axis intelligence had overestimated the British armoured strength by 40% and the infantry strength by 45%.

'Cascade' provided the Allies with invaluable experience in the planning and execution of deception operations, and this was important in the development of the various deception operations, such as 'Fortitude', associated with the invasions of Europe ('Overlord' in Normandy and 'Dragoon' in southern France).

The supposed British formations carefully built up during 'Cascade' were later reused in 'Zeppelin' to tie down Axis formations in the Balkans and thereby prevent the Axis powers from redeploying these formations against the 'Husky' (i) invasion of Sicily. In 1944 the actual Allied strength in the Mediterranean totalled some 52 divisions, but Axis intelligence was confident that there were about 70 divisions in the theatre.