Brigadier Dudley Wrangel Clarke, CB, CBE (27 April 1899 – 7 May 1974) was an officer in the British Army, known as a pioneer of military deception operations during the Second World War.

[3] During the Second World War, Clarke joined John Dill's staff, where he proposed and helped to implement an idea for raids into France – an early form of the British Commandos.

In 1912, he attended Charterhouse School, where he was exposed to the glamorous parties and smart uniforms of the nearby military presence at Aldershot, including the newly formed Royal Flying Corps.

To his own surprise (he had petitioned the Charterhouse headmaster for a recommendation, allowing him to bypass the exam, on the expectation of failing), he passed and in early 1916 attended the Royal Military Academy, Woolwich.

Clarke volunteered to help the local British force and was tasked with feeding misinformation to Turkish nationalists – a first taste of the activities that would define his later military career.

The British presence in Jerusalem was minimal at that time, comprising two battalions of infantry and a motley collection of air and armour under the command of Colonel Jack Evetts.

In 1937, Dill was replaced by Major-General Archibald Wavell, the commander who would later give Clarke free rein in Middle Eastern deception operations.

He worked with Wavell in the Middle East to research possible Allied supply lines, undertook two trips to Norway (in an effort to maintain its neutrality), and conducted secret missions in Calais and Ireland.

On 30 May 1940, inspired by childhood recollections of similar Boer forces as well as experiences during the Arab uprising in Palestine, Clarke sketched out an idea for small amphibious raiding parties, called Commandos.

[20] By March, Clarke had another scheme in the works, a deception cover for Operation Cordite, the 6th Infantry Division invasion of the Greek island Rhodes.

Clarke gave the project his full backing, and the unit was named "L" Detachment, Special Air Service – in part to help solidify the existence of the larger fictional force in the minds of the enemy.

[20][23] Phantom forces, of which the SAS was only Clarke's first, played a crucial part in deception operations during the war – including along the Western Front in 1944 – but for the rest of April 1941 he worked hard to build his department.

In Wolfson, Clarke had found an important resource and, in his own words, began "a long and profitable partnership for Deception and MI9 matters in Turkey which was to last for the rest of the war".

[24] Clarke left Istanbul on 16 May, travelling covertly back to Egypt via Syria and Lebanon in order to reconnoitre the ground that British forces would have to invade when entering the country.

He declined, citing loyalty to the Middle East, but his decision was in large part due to the greater operational freedom and status he enjoyed in North Africa.

Before leaving for the Eighth Army headquarters in Gazala, Clarke left a note, which he later described as "begging for the whole question of deception machinery in the Command to be reviewed completely afresh during his absence.

The plan, which involved Victor Jones creating a strong fictional force of 300 tanks on the British right hand flank, was in full swing during February.

Auchinleck rallied his forces at El Alamein and asked Clarke to draft plans for delaying the Axis advance, giving the Allies time to withdraw.

Operation Sentinel was designed to convince Rommel, using camouflage, fakery and radio deception, that substantial British armour sat between him and the retreating Eighth Army.

Montgomery knew Clarke, having taught him infantry tactics at the Staff College in 1931, and instructed him to prepare deception plans for the Second Battle of El Alamein.

The meeting agreed on plans for a disinformation campaign, which would attempt to convince German high command that the Allied targets in Africa were Dakar and Sicily (the far eastern and western limits of the theatre).

Barclay was the elaborate deception with which Clarke was tasked, an operation to mislead the Axis into expecting attacks on the far eastern and western extremities of the northern Mediterranean theatre – namely the Balkan Peninsula and southern France.

Building on Cascade he added the Twelfth Army to his fictional order of battle, and began to make them look like a convincing threat to Crete and the Greek mainland.

[39] On 14 October he was appointed Commander of the Order of the British Empire (CBE), the citation (marked "not for publication") praised Clarke's ongoing work, referring to him as "irreplaceable".

Bevan and the London Controlling Section were tasked with inventing an elaborate masquerade to cover the Normandy invasion, a vindication of the theory pioneered by Clarke and Wavell: that every real operation should have a complementary deception.

In April 1945, Clarke left Cairo for London; on 18 June he called a meeting of the remaining 'A' Force members at the Great Central Hotel where the department was disbanded.

[9][49] Clarke lived out his retirement in relative obscurity, despite the belief of his former commander, Field Marshal Harold Alexander, that "he did as much to win the war as any other single officer".

From another early operation (K-Shell, the spreading of rumours about a new Allied super-shell which eventually petered out after the media picked up the story), he learned the value of conducting deception only when there was a clear objective, rather than because it was possible.

[4][56] Despite having middle-class origins, he aspired to the fringes of the upper-class establishment, in his words: "one of those in the inner circle, watching the wheels go round at the hub of the British Empire at some great moment in history.

While at flight school in Reading, and without any money to fund his recreation, he built "an apparatus composed of a bootlace, a lanyard and some straps off my valise, by which I am enabled to turn out the light without getting out of bed".