OSS/London

OSS/London
51, 70, and 72 Grosvenor Street, Mayfair, London
Area of Grosvenor Street as it looks in 2016
Site information
Type	Headquarters
Owner	Office of the Coordinator of Information Office of Strategic Services
Operator	Special Operations Branch Secret Intelligence Branch Field Photographic Branch Research and Analysis Branch Maritime Unit Operational Group Command
Controlled by	United States
Location
Coordinates	51°30′42″N0°08′45″W / 51.511711409544965°N 0.1457877379902936°W / 51.511711409544965; -0.1457877379902936
Site history
In use	1941-1945
Battles/wars	World War II
Garrison information
Occupants	Isaiah Sol Dorfman

OSS/London was the largest foreign headquarters complex of the Office of Strategic Services (OSS) during World War II, operating out of several buildings in the area near Grosvenor Square, Mayfair, London, which maintained the command and control over all OSS servicemembers stationed in the United Kingdom and agents deployed to Western Europe. ^[1] From Grosvenor Square, operations were planned alongside the British Secret Intelligence Service (MI6) and the Special Operations Executive (SOE) to deploy officers and agents throughout Europe for missions of sabotage, clandestine operations, covert operations, espionage, and other mission sets. ^{[2] [3]} OSS/London began as London Outpost with a single staffer from the Office of the Coordinator of Information (COI) assigned as a Liaison officer to the British government. At its peak staffing in 1944, there were 2,800 OSS personnel working under the command structure of OSS/London. ^[4]

History

Throughout 1939 and 1940, President Franklin Roosevelt and Winston Churchill were in constant communications, where Churchill tried to convince Roosevelt to contribute militarily to the war. Roosevelt could not do this without an Act of Congress. ^[5] However, in June 1940, he did deploy William J. Donovan to London on a fact-finding mission to gauge British strength, and to discover any information regarding fifth columns. While Donovan was in England, he formed relationships with Stewart Menzies, King George V, John Henry Godfrey and Ian Fleming. Upon his return to the United States, Donovan presented his findings to Roosevelt that they were in desperate need of a new style of civilian intelligence agency, to be modeled after the British system. ^[6]

In July 1941, Roosevelt appointed Donovan as the head of the Office of the Coordinator of Information (COI). After the British officers Dick Ellis and Ian Flemming contributed to the blueprint for the agency, the first batches of COI-trained operators were sent to Camp X, which was operated by the Special Operations Executive (SOE), whose first commandant was Richard Melville Brooker. ^[3]

COI quickly began establishing liaisons and forward bases around the world, especially utilizing the existing intelligence sharing networks of several federal agencies such as the Federal Bureau of Narcotics (FBN) and the Secret Service.

At the end of 1941, Donovan and the COI established the London Outpost. ^[3]

In June 1942, the SO and the SOE signed the "SO/SOE agreement." ^[7]

On 10 January 1944, the SO/London and the London Group were merged into Special Forces Headquarters, under which they continued their activities.

Between January and September 1944, a total of 93 Jedburgh teams, each composed of one British SOE member, one American SO officer, and one officer native to the country of operations—were parachuted into occupied Western Europe to assist resistance movements and coordinate clandestine operations. ^[3]

Activities

The Special Operations Branch at OSS/London, known as SO London, was responsible for sabotage, the supply and support of resistance organizations, and the conduct of guerrilla warfare in enemy-occupied areas. Its British counterpart was the SOE’s “London Group.” ^[3]

The Secret Intelligence Branch at OSS/London was tasked with the collection and analysis of strategic intelligence in support of the U.S. Joint Chiefs of Staff. ^[3]

The OSS was formally dissolved by Executive Order 9620 on 20 September 1945, leaving the facilities at Grosvenor Street to eventually become residental complexes. ^[3]

References

1. "Records of the office of Strategic Services [OSS]". www.archives.gov. (226.17.3 Records of the London Base). Retrieved 2025-12-22.
2. Gould, Jonathan S. "The OSS and the London "Free Germans"". www.cia.gov. Archived from the original on 2017-03-12. Retrieved 2025-12-22.
3. "Microform: OSS/London: Special Operations Branch and Secret Intelligence Branch War Diaries - AIM25 - AtoM 2.8.2". atom.aim25.com. King's College London. Retrieved 2025-12-22.
4. MacPherson, Nelson (2003-03-30). American Intelligence in War-time London: The Story of the OSS. Routledge. ISBN   978-1-135-77246-8.
5. "Churchill Offers Toil and Tears to FDR". AMERICAN HERITAGE. Retrieved 2025-12-23.
6. "William "Wild Bill" Donovan: America's Spymaster in WWII". Warfare History Network. Retrieved 2025-12-23.
7. United States. Office of Strategic Services (1976). War report of the OSS (Office of Strategic Services). Internet Archive. New York : Walker. ISBN   978-0-8027-0539-6.