COSSAC

COSSAC, acronym derived from the title Chief of Staff to the Supreme Allied Commander, a position held initially by Lt- General Frederick Morgan. It was also commonly used as the name for the organization headed by Morgan.

The decision to appoint a chief of staff was taken at the Casablanca conference in January 1943 (see SYMBOL) so that planning for an invasion of the Continent in 1944 could proceed, and the nucleus of an operational HQ could be established for the Supreme Commander designate. Morgan was appointed in March and set up his HQ in Norfolk House, St James's Square, in central London, with an Anglo-US staff. His directive called for him not only to plan the invasion, but for his Ops B section to implement a deception scheme (COCKADE) that would keep the Germans alert for landings in 1943. Three such schemes were operated as part of COCKADE: landings on the Brest peninsula (WADHAM), an attack on Norway from Scotland (TINDALL), and landings in the Pas-de-Calais (STARKEY). Morgan also had to prepare plans (RANKIN) to invade immediately if the circumstances merited it.

COSSAC's outline plan to land in Normandy (see OVERLORD) was approved at the Quebec conference in August 1943 (see QUADRANT) and the detailed planning for it was then passed to the staff of the commanders of land, air, and sea forces taking part. Morgan, who was given increased powers, now became the driving force for OVERLORD, and for the many tasks related to it. These included such matters as intelligence, subversive warfare, meteorological intelligence, the preparation of prefabricated harbours (the MULBERRIES), the installation of cross-Channel fuel lines (see PLUTO), and civil affairs. The last of these caused such heated discussions between London and Washington that Morgan remarked that ‘there were plenty of affairs but the difficulty was to keep them civil’.

In December 1943 Eisenhower was appointed Supreme Commander. As he wanted Lt-General Bedell Smith as his chief of staff, Morgan became one of Smith's three deputies at Eisenhower's Supreme Headquarters Allied Expeditionary Force (see SHAEF) which absorbed nearly all COSSAC's staff when it was formed in February 1944. Morgan, Eisenhower later wrote, made Normandy D-Day possible.

Bibliography

Morgan, F. E. , Prelude to Overlord (London, 1950).