From Operation Mincemeat: How a Dead Man and a Bizarre Plan Fooled the Nazis and Assured an Allied Victory, by Ben Macintyre (Crown, 2010), Kindle pp. 102-104:
A cable was sent to Captain Alan Hillgarth, the naval attaché at the Madrid embassy and Churchill’s intelligence chief in Spain, asking him to send a trusted lieutenant to London for an urgent conference. Salvador Augustus Gómez-Beare, assistant naval attaché at the British Embassy in Madrid, duly presented himself at the Admiralty, fresh off the plane from Madrid, and was ushered into Room 13.
Gómez-Beare, universally known by his nickname “Don,” was an Anglo-Spaniard from Gibraltar who perfectly straddled the two cultures. He was a British citizen, enjoyed a large private income, spoke pure upper-class English, and displayed impeccable English manners and habits as only someone who is not English can. He played bridge with Ian Fleming at the Portland Club and golf all year round. But in Spain he was Spanish and brown-skinned, spoke with a southern accent, and was invisible. In 1914, as a medical student in Philadelphia, he had volunteered to join the British army, and spent two years in the trenches before joining the Royal Flying Corps. During the Spanish civil war he had “worked in military intelligence for Franco’s army.” Gómez-Beare could reach places no Englishman could penetrate, “a Spaniard to Spaniards and an Englishman to the English, who served England with an intensity and thoroughness that no mere Anglo-Saxon could attain.” Hillgarth had recruited him in 1939, initially suggesting he be given the rank of captain in the Royal Marines “because of his enormous RAF moustache.” He was given the rank of lieutenant commander in the RNVR on condition he shave and despite having “no more than a smattering of sea experience,” but from the start of the war, Gómez-Beare could be found “padding about Madrid, driving up to San Sebastian, flitting over to Barcelona, hovering about Gibraltar, and smuggling British airmen out of France.” When Airey Neave escaped from Colditz in 1942, it was Gómez-Beare who smuggled him across the border to Gibraltar. He had a villa in Seville, a flat in Madrid, and spies in every corner of Spain. Gómez-Beare was Hillgarth’s primary recruiter and runner of secret agents.
Alan Hillgarth, as a senior member of the embassy staff in a neutral country, could not be seen to engage directly in espionage or recruit spies, but Gómez-Beare was under no such constraints. In Hillgarth’s words, he was “exceptionally favoured by character40 and linguistic attainments to cultivate such people, and in the majority of cases his contacts would not have agreed to work with anyone else.” Gómez-Beare’s spies ran through the Spanish bureaucracy like veins through marble: he had agents in the Spanish police, the security service, the Ministry of the Interior, the General Staff, and every branch of the military. He had informants in high society and low, from the salons of Madrid to the docks of Cádiz. These spies never met one another and only ever made contact through Gómez-Beare himself. “He was invaluable,” said Hillgarth. “It was he who handled our special contacts. His loyalty and discretion are unequalled and the Spaniards, particularly the Spanish Navy, love him.”
The Germans, by contrast, did not love Don Gómez-Beare. Britain’s assistant naval attaché narrowly escaped being blown up by a car bomb during a clandestine visit to Lisbon. Madrid was a festering nest of espionage and counterespionage, and for four years a fierce war had raged between British spies and German spies in Spain, undeclared, unofficial, and unrelenting. Both sides deployed bribery and corruption on a lavish scale. Abwehr agents spied on their British counterparts, who responded in kind; the Spaniards spied on both sides, rather inefficiently. At first, the odds seemed stacked against the British. The Germans simply had too many advantages, with numerous “privileges and facilities (of course unofficially)” provided by willing Spanish collaborators. The Abwehr infiltrated all branches of the civil service, police, government, and even business. But with time, the contest leveled out, as Hillgarth and Gómez-Beare extended their web of informants through a combination of charm, bribery, and skulduggery. “Spain contained a large number of German agents and plenty of Spaniards in German pay,” wrote Hillgarth. “They had some ingenious ideas. We did our best to learn their plans, and to some extent succeeded.” In this febrile atmosphere, it was impossible to be sure who was spying for whom. “Madrid was full of spies,” wrote Hillgarth. “No one is watched all the time, but everyone is watched some of the time.”
And no one was watched more closely, or better at watching, than Don Gómez-Beare.


