The Secret War: Spies, Codes and Guerrillas 1939–1945. Max Hastings

still lay in the future, and he was seen in Whitehall simply as a pushy young ‘boffin’ who seemed too free with his opinions in the presence of senior officers. Jones, almost alone, elected to believe that the Oslo document was authentic. His instinct became a near-certainty in the summer of 1940, when the Luftwaffe began to use the Wotan navigational beam to guide its bombers over Britain, exploiting principles mentioned by Oslo’s author. R.V. Jones, as he is known to posterity, found the information invaluable in devising counter-measures during the ‘Battle of the Beams’ that influenced the Blitz – which gained him the ear and the admiration of Winston Churchill. Again and again through the years that followed, when the British gained hints about new German weapons – the acoustic torpedo, for example – Jones was able to point out to service chiefs that Oslo had warned of them. After the war, in a retrospective on his own intelligence career, the scientist used the example of the 1939 document to urge that ‘casual sources should not be treated flippantly. It was probably the best single [scientific intelligence] report received from any source during the war.’

      Only after an interval of almost forty years did Jones establish the document’s authorship. It was the work of a forty-five-year-old German physicist named Hans Ferdinand Mayer, who adopted a scientific career after being badly wounded on his first day in action as a conscript in 1914. He had been employed by Siemens since 1922, doing work that resulted in the award of eighty-two patents and the publication of forty-seven papers, and also spent four years as professor of signals technique at America’s Cornell University. During the inter-war years he formed a warm friendship with an Englishman working for GEC named Cobden Turner, who became godfather to Mayer’s second son. The German was especially impressed by a good deed: when he told Turner about the tragic case of a Jewish schoolchild disowned by her Nazi father, the Englishman arranged for the little girl to come to England, where for eight years she lived as a member of his own family.

      When the international horizon darkened, on what proved Turner’s final visit to Germany Mayer told him that if war came, he would try to supply Britain with information about German scientific and technological progress. In late 1939 the scientist exploited a chance business trip to Norway to make good on his promise. He borrowed an old typewriter from the porter at the Hotel Bristol and composed the ‘Oslo Report’, which was dispatched in two parts to the British embassy on 1 and 2 November. Mayer also wrote directly to Cobden Turner, suggesting further contact through an intermediary in neutral Denmark. But although this letter caused two British security officers to visit and question the GEC man, for reasons unknown nothing was done to open communication with Mayer – MI6’s official history makes no mention of this courageous German. In August 1943 Mayer was arrested by the Gestapo in his office at Siemens, and charged with listening to the BBC. He was confined in Dachau, but was fortunate enough to be employed in a technical plant, where he survived the war. His brave gesture was prompted by admiration for Cobden Turner, whom he liked to regard as a representative Englishman. Recognition of Mayer’s contribution, however, came only from Reg Jones.

      Among the reasons the ‘Oslo Report’ received such a chilly reception is that it was debated in Whitehall just as the British secret community reeled in the wake of a successful German ruse. On 9 November 1939, during the first, passive phase of the war that became derisively known as the ‘sitzkrieg’, the two senior MI6 officers in the neutral Netherlands, Captain Sigismund Payne Best and Major Richard Stevens, drove with a Dutch officer in Best’s Lincoln Zephyr car to a rendezvous at the Café Backus, situated between the Dutch and German border customs barriers at Venlo. Within minutes of their arrival, they were seized by armed men. When the Dutchman drew a pistol and fired at one assailant, he was himself shot dead. Best, Stevens and their local driver were then hustled 150 yards to the frontier: their kidnappers were Nazi counter-intelligence officers of the SD, led by the branch’s later boss, Walter Schellenberg, who was narrowly missed by the Dutch officer’s bullet. The British spies were fortunate enough to keep their lives, but spent most of the rest of the war in Sachsenhausen concentration camp. In contradiction of myths about heroic silence under interrogation, Stevens and Best told their abductors what they knew about MI6, which was plenty: its Continental operations were chiefly conducted from their own Hague station.

      ‘The Venlo incident’, as it became known in Whitehall, derived from an approach some weeks earlier by supposedly anti-Nazi German generals eager to negotiate with Britain. MI6 became much excited by the prospect of brokering a deal, though the Foreign Office was prudently sceptical. Sir Alexander Cadogan wrote in his diary on 23 October: ‘I think they [the German “plotters”] are Hitler agents.’ The war cabinet was informed a week later, and Winston Churchill, then still First Lord of the Admiralty, expressed violent objections to any parley. But the government authorised MI6 to continue discussions, provided – as Cadogan strictly instructed – nothing was put in writing to the supposed dissidents. The British ignored the danger that their interlocutors would play not merely a diplomatic game with them, but a rougher one. They should have been alert to such an outcome, because the Nazis had previous form as cross-border kidnappers: in April 1934 they had lured to the German frontier a Czech intelligence officer, twenty-nine-year-old Captain Jan Kirinovic, then rushed him across. A Gestapo witness gave evidence at Kirinovic’s subsequent trial that he had been arrested on German soil, and Kirinovic was sentenced to twenty-five years’ hard labour. Although in the following March the Czech officer was exchanged for two German spies, he died insane a few years later as a result of the drugs administered to him by the Gestapo, notably scopolamine.

      In November 1939, it was symptomatic of MI6’s institutional weakness that its Hague station employed Folkert van Koutrik, an Abwehr informant. The supposed representative of the disaffected German generals, ‘Major Schaemmel’, was in truth the RSHA’s Schellenberg, whom the British officers obligingly supplied with a wireless transmitter. Either Hitler or Himmler personally authorised the kidnapping, which the British at first sought to keep secret. When an official asked Cadogan what was to be said about ‘the brawl in Holland’, the subject of fevered rumour and speculation, the permanent under-secretary ordered the issue of a ‘D’ Notice, forbidding mention of it in the British press. Amazingly, for a fortnight after Venlo the German ‘conspirators’ sustained a dialogue with MI6, until on 22 November Himmler lost interest and the Germans shut down the exchange after sending a last derisive message to Broadway. The Nazis then publicly announced that Best and Stevens had been engaged in an assassination plot against Hitler. Meanwhile van Koutrik’s betrayal went so far undetected that he secured employment with MI5 in London, and it was very fortunate that he broke off contact with the Abwehr – perhaps for lack of means of communication – because it was within his later knowledge to have betrayed elements of the Double Cross system to them.

      Inside Whitehall, MI6 sought to talk down Venlo, arguing that the Germans had behaved crassly by grabbing the two officers instead of sustaining a double-cross game with them. It is hard to overstate the episode’s significance, however, for the future course of the secret war. British espionage activities on the Continent, such as they were, suffered a devastating blow: the Germans were able to relieve Best of a list of his station’s contacts, which he had taken in his pocket to the rendezvous. The reputation of the secret service within the British government, not high before the débâcle, afterwards sagged low indeed. Guy Liddell of MI5 speculated in his diary that Best, a preposterous figure who affected a monocle, might have been a double agent – ‘the real nigger in the woodpile. [He] had apparently been in fairly low water and it was noticeable that after he became associated with [Dr Franz] Fischer [a Nazi double agent in Holland] he seemed to be very well in funds.’ There is no reason to think Liddell’s suspicions justified. Mere bungling was responsible for the fiasco, though Walter Schellenberg asserted later that Best was willing to be ‘turned’. Meanwhile, the Dutch were embarrassed by the revelation that one of their own intelligence officers had been complicit in a British plot, which strengthened the Nazis’ propaganda hand by compromising Holland’s proclaimed neutrality.

      A further consequence of Venlo was that the British became morbidly suspicious of any approach – and there were several, later in the war – by Germans professing to represent an ‘anti-Hitler Resistance’. In one sense their caution was prudent, because most of the aristocrats and army officers who became engaged in plots against the Nazis cherished absurd fantasies about the Germany they might preserve through