As you will know, many of the Ahnenerbe expeditions were attempts to find evidence for an Aryan precursor civilization, to substantiate the Nazi fantasy of an Aryan master race. Even within the Ahnenerbe there were many who knew this was absurd, but who could see it as a useful cover for the more plausible business of searching for Jewish treasures from antiquity lost or concealed around the world. Prime among their interests was the Ark of the Covenant. To find that, to bring it back to Germany and display it in Berlin, would have been the ultimate symbol of dominance over the Jews. That was what most worried our intelligence people about the Ahnenerbe, and it went to the very top. Churchill had little interest in fantasies of an Aryan master race, but he was deeply concerned about anti-Semitism, about the way Hitler and his cronies used it to stir up and strengthen Nazi belief. Once when he visited us he said that the discovery and parading in Berlin of a single artifact from the Temple in Jerusalem would be the equivalent of losing two or three army divisions to the Nazis, such would be its effect on German military morale. The horrible consequences of Nazi anti-Semitism were also becoming known. By 1943 we were aware of the mass murder of Jews by the SS Einsatzgruppen in the east, and reports of death camps in Poland were beginning to gain credibility.
By then the Americans were of course major players in the war; the American Jewish lobby had been a powerful factor in pushing Roosevelt to commit against Hitler in the way he did. Few people realize how much Churchill worked his will on those people during his early visits to America, and how grateful he was to them. For us in Allied intelligence to have failed to prevent an artifact central to Jewish identity from reaching Nazi Germany would have been a terrible blow. Hitler would have presented it as a huge triumph, just like the Roman emperor parading the spoils of the Temple through Rome after the sack of Jerusalem. He would have used it to try to humiliate and degrade the Jewish people. Imagine the scene: goose-stepping SS officers carrying the Ark past the Reichstag just like the legionaries shown with the menorah at the Arch of Titus in Rome, and the Ark then being defaced or destroyed. It would have been ghastly. Churchill by this stage in the war had taken many decisions for the greater good that required our men knowingly or unwittingly to sacrifice their lives, and Operation Ark would be one of those.
Whether or not the Ark had truly been found by Ahnenerbe agents we may never know. But the intelligence was good enough to put our intelligence people in South Africa on it. Nazi agents were often clumsy and obvious, and we’d rumbled the Durban operatives before the war even began. Our people determined that something had been secreted on board the British merchant ship Clan Macpherson during her port stay at Durban in mid-April 1943. After she sailed, only two days before her sinking, one of the Nazi agents was snatched and interrogated. He revealed that the plan had been an elaborate set-up involving another Nazi cell in Bombay, one that we had not previously rumbled. A month earlier, Clan Macpherson had stopped there and picked up a new draft of Lascar seamen, among whom were six former Indian Army sepoys who had gone over to the Japanese in Burma to join the Indian National Army against the British.
We now know that the Nazis, with Japanese assistance, recruited a number of these Indian nationalists for nefarious purposes; this was one of the few plans that came close to fruition. The six men were experienced soldiers trained in unarmed combat who were meant to kill the ship’s gunners, arm themselves, and take over the bridge. This was to happen at the coordinates we had learned from the Enigma decrypt mentioning Ark, when the ship was part of convoy TS-37 halfway between Takoradi and Sierra Leone. The usurpers were to slow the ship to cause her to straggle behind the convoy, and to signal engine trouble to the escorts. That would allow U-515 to distinguish her from the other ships when it attacked the convoy. The captain of U-515 was ordered to hit as many ships as possible, so that the escorts were entirely focused on the threat amidst the main body of the convoy and on picking up survivors. The U-boat was then to slip back, rendezvous with Clan Macpherson and take off her precious cargo and the six men. After standing off, she would torpedo the ship and machine-gun any of the crew who happened still to be alive in the water. She was then to rendezvous in the mid-Atlantic with a supply boat, U-409, that was to take the cargo directly to the U-boat base at Lorient on the French coast, at which point the precious cargo would be flown on to Berlin.
Ian was able to tell me all this because Churchill had personally selected him to be part of a directive within Bletchley whose remit encompassed the Ark operation. Enigma intelligence, as you know well, was Ultra, for ultra top-secret; this organization was one stage of secrecy above that, and never had a name. The only others in on the operation at Bletchley were Captain Pullen, who you will remember, Alan Turing and another cryptographer, and me. I was recruited by Ian just before TS-37 was hit, so I was with him when he put through the call that sealed Clan Macpherson’s fate, though not as the Nazis had envisaged it. Unknown to me, Churchill had vetted me already when he spoke to me during one of his covert visits to Bletchley a month or so earlier.
I mentioned that there was a bigger picture, the wider remit for our group that Ian and I agreed never to speak about; the operation against the Ahnenerbe was, if you like, a fold within that picture, though closely intertwined with it. All I can say is that because of that wider remit, we already had in place a line of specialized hunter-killer submarines off the west coast of Africa, one of them off Sierra Leone. By the time we knew of the Ark plan from the interrogation of the Nazi agent in Durban, it was too late to warn Clan Macpherson; without knowing the names of the six men, it would have been impossible for the captain to take effective action, and worse still, it might have alerted B-Dienst that we were on to them and had possibly broken Enigma.
Churchill himself made the final decision. Our submarine would shadow the convoy, wait until it saw a ship straggling, and then torpedo it. With U-515 meanwhile embarking on its attack on the main body of the convoy to the north, nobody would be any the wiser. History would record Clan Macpherson as just another one of U-515’s victims on that terrible night. Whatever the treasure was, whether or not it was the Ark, would be lost forever, and another small victory would have been scored against the Nazis, unknown to history and cloaked under a veil of secrecy that would see almost all of those in the know taking the story with them to the grave.
And that’s what happened. Clan Macpherson went down at about 0540 on May 1. The takeover by the six men was put down to a mutiny by disaffected Lascars influenced by the Indian nationalist movement, at a time when Lascars on other British merchant ships were refusing to serve in the North Atlantic. Even so, the survivors were met by naval intelligence officers who had been flown out to Freetown to swear them to secrecy for reasons of national security, on the grounds that knowledge of a mutiny would be utilized for propaganda by the Nazis and might result in even more widespread disaffection among the Lascars, a potential disaster at that critical point in the Battle of the Atlantic. The captian of Clan Macpherson, who survived the sinking, agreed to go along with it, and to write critically to the trade division at the Admiralty about the weakness of the convoy escort in order to deflect any wayward attention from the circumstances of Clan Macpherson’s sinking, the reason why she might have fallen back behind the convoy.