Operation Ironside

Operation Ironside was a Second World War military deception. Undertaken by the Allies in 1944, the operation threatened an invasion of France, along the Bay of Biscay, in support of the invasion of Normandy. Ironside formed part of the Operation Bodyguard deception strategy.

Planning for Ironside fell to the London Controlling Section, with the operation carried out via double agents. It was intended to play on German fears of an invasion in the Bordeaux region, with the aim of tying down defensive forces there. As with many of the Bodyguard deceptions, the force earmarked for Ironside never existed. The storyline for the supposed invasion included an initial two-division assault from the United Kingdom, followed by a further eight divisions sailing from the United States. Agents Tate, Bronx and Garbo relayed snippets of the plan to their German handlers during May 1944.

There is no indication that Ironside was successful in convincing the Germans of Allied plans to invade the Bay of Biscay. Worried about exposing agents as false, the Twenty Committee sent disinformation with words of caution. In addition, Allied landings around Bordeaux were implausible because it was beyond fighter cover from the United Kingdom.

Background
Operation Ironside formed part of Operation Bodyguard, a broad strategic military deception intended to confuse the Axis high command as to Allied intentions during the lead-up to the Normandy landings. The overall aim of Bodyguard was to tie down German forces away from Normandy, by threatening a number of other targets. Ironside's objective was to tie up the 17th SS Panzer Division in the south of France.

Overall planning for Bodyguard, and Ironside, rested with John Bevan and the London Controlling Section (LCS). The LCS had been set up in 1942 following successes in deception in the Middle East by Dudley Clarke. After some initial attempts at deception planning, the department was tasked with bringing Bodyguard to fruition.

In January 1944, the Allies intercepted communications indicating that German commanders were concerned by the possibility of landings in the Bay of Biscay region of France. During February, German naval and air units undertook anti-invasion exercises in the area. Ironside was intended to amplify these concerns.

Planning
The plot for Ironside was that, ten days following D-Day, Allied forces would land in the Bordeaux region, around the Garonne estuary. This force would establish a bridgehead before advancing to meet Operation Vendetta formations (another deception operation targeting the Mediterranean coast of France).

At first, Bevan suggested that the fictional invasion force should stage from America, but it was decided this would be implausible. In the end it was agreed that a realistic threat would be to stage an initial assault with two divisions from the United Kingdom, landing a further six divisions direct from the East Coast of the US once a bridgehead had been established. The chosen divisions were the 26th, 94th, 95th, and 104th Infantry, and the 10th and 11th Armored. Lieutenant General Lloyd Fredendall was chosen as the force's commander.

Operation
Ironside was implemented entirely via double agents, under the control of the Twenty Committee. On 23 May, agent Tate (Wulf Schmidt) sent a message to his handlers saying that a friend from the US had identified an expeditionary force, consisting of six divisions, preparing to sail.

On 29 May, agent Bronx sent a coded telegram identifying an invasion targeted at the Bordeaux region within a week. She also sent a follow-up letter explaining that the information came from a drunken British officer in the Four Hundred Club, and that he had later sworn her to secrecy, adding that the operation had been delayed by a month. In June, agent Garbo, one of the most important Allied double agents, passed on a report from one of his fictional sub-agents that US divisions had arrived in Liverpool, and were preparing to head to Bordeaux.

The Twenty Committee considered that Ironside was quite implausible, and as a result was cautious about using agents to promote it too heavily. Most of the messages were sent with words of caution or uncertainty, to ensure that the asset would not be compromised. Garbo explicitly noted that he was unsure of his informant, and skeptical of the report.

Impact
German intelligence documents indicate that there was never any strong belief that the Allies would land in the Bordeaux region. Prior to Ironside's execution Axis commanders had considered the idea, and conducted exercises in preparation. Following the deception, intercepted situation reports suggested that the Germans believed rumours of landings in the area to be "cover operations of small caliber". In fact they believed them part of the cover for a main Allied thrust at Calais, in itself a deception called Operation Fortitude South. Although training continued in the region, and the 17th SS Panzer Division was delayed in mobilizing to Normandy, it appears that the Germans did not consider landings very likely. Part of the problem was that Bordeaux was not a plausible Allied target, because it was out of the range of fighter cover from the United Kingdom.

Ironside II
The premise of Operation Ironside was reused in July 1944, in support of Operation Ferdinand. Because of the vague interest in the original operation by German intelligence, the LCS had continued to promote the idea of an invasion after 28 June (when the initial deception was supposed to have ended). Agent Rudolff sent messages on 10, 12 and 18 July referring to the Ironside force.

In mid July, the Allies began deception activities to cover Operation Dragoon, the August invasion of southern France. After some discussion (Noel Wild and Ops (B), the SHAEF deception planners, were worried about the impact on the continuing Fortitude deception) it was decided that a new story would be presented to the Germans. It would suggest that the Allies intended to bolster French resistance in the south of the country, seizing Bordeaux to facilitate the landing of heavy weaponry.

Again, the deception was implemented via double agents, mostly by reporting the arrival of heavy machinery and bridging equipment in New York, where the invasion force was based. The operation went largely unnoticed and German interest in the Bordeaux region dissipated.