THE COMING BATTLE was not initiated on land, but in the North Atlantic.
The Captain’s log read ‘9 December 1944, 27th Day at Sea. On station, map square AK 5226’. The conditions were appalling. Outside, the green sea boiled like an erupting volcano as the bows emerged – like a knife of dark metal in an unfriendly sea, and then the periscopes, dripping. Next the conning tower pierced the surface at a crazy angle and icy spume cascaded down as the submarine clawed its way to the surface. Mountains of water heaved and flung themselves madly at the sky. The craft rolled uncomfortably as waves pummelled her hull. While U-1232wallowed, four crewmen tumbled on to the bridge. Gusts of wind bearing sleet and snow cut into their faces like needles. With smarting eyes, the watch scanned every compass point: torn, menacing clouds, no horizon and little visibility though it was midday. It was unhealthy for a U-boat to remain long on the surface, but aircraft were far from their thoughts. No flyer could survive such a storm.
Since leaving Horten in Norway, U-1232 had been discreet, running submerged on her silent electric engines and surfacing only at night, using her diesels to recharge the batteries. The swifter, air-breathing diesels would have exhausted the crew’s oxygen and were useless underwater, unless they used the snorkel, a device that allowed them to travel submerged – and hidden – while drawing in air to feed the hungry diesels. In such a storm snorkels were redundant. So the Type IXC U-boat had crawled along on her twin electric motors at five knots, the speed of a man on a bicycle, when she could easily have made fifteen on the surface. After twenty-seven days of no washing, U-1232’s crew of fifty welcomed any opportunity for fresh air, even if storm-tossed with cold water streaming through the conning tower hatch every few seconds.
On his way to hunt the waters off Halifax, Nova Scotia, forty-year-old Kapitän zur See Kurt Dobratz had been given an important mission. Although carrying twenty-two torpedoes, he was not after Allied shipping – for the time being. Since the gradual capture of its weather ships, the Third Reich had been weather-blind. For some reason beyond Dobratz’s knowledge U-boat Kontrol in Berlin was keener than usual on meteorology. His submarine was one of four despatched to send back weather reports from the North Atlantic. Days earlier his admiral, Eberhard Godt, the Befehlshaber der Unterseeboote (Commander of Submarines), had radioed him ‘weather reports are of the greatest importance for the war on land and in the air’. Another reminder of the following day read ‘Importance and seriousness of task demands that all means be used to get messages through’. The Allies intercepted both messages and pondered. Dobratz must have known something was afoot and was anxious not to screw up his first war patrol. Although trained as a naval officer, the already highly decorated officer had spent eight years attached to the Luftwaffe, with eleven combat sorties in bombers under his belt, and understood the importance of accurate climatic returns.
As each broadcast increased the risk of detection by Allied direction-finding, Dobratz crammed as much information as possible into his signal, which consisted of no more than two dozen letters, each representing a certain measurement – barometric pressure, cloud cover, wind strength and direction, visibility, air temperature, and so on. The Allies as well as Kontrol, he knew, would be waiting for his report, and use it to hunt him down. Thrown about in the conning tower, doubtless with numb fingers by this point, the watch took the necessary readings quickly and sent them below to the radio operator, who swiftly encoded them using his Enigma machine. Shortly after, a Wetterkurzschlussel (short weather signal) of only a few seconds flew across the airwaves via relay stations to Berlin. Knowing that Allied destroyers would now be vectored on to his position, he moved away quickly, ready to report again in twelve hours’ time. Job done, U-1232 slunk beneath the furious waves.
In Koralle (‘Coral’), codename for the bunker complex of U-boat headquarters at Bernau, five miles north of Berlin, the report was read impatiently. Cloud, fog, driving snow, freezing temperatures were all welcome news. Dobratz’s information corresponded to that of the other weather-reporting submarines and the eleven-strong team of Operation Haudegen, a land-based weather station on the Norwegian island of Spitzbergen. A cold weather front of intense severity was moving towards Europe and would arrive within the week. It was just what the Fatherland needed.
In Berlin, Dr Karl Recknagel, the Kriegsmarine’s chief meteorologist, analysed these and other reports. Back in November the head of the Luftwaffe’s Weather Office, Oberstleutnant Werner Schwerdtfeger and his deputy, Major Dr Schuster, had been summoned and given a well-nigh impossible task:
two days before the occurrence in the coming month of December, you have to forecast the date of a period of five days or more in which fog or low clouds will continuously cover a wide area of the Rhine River north of the 50° parallel, including the region of the Ardennes and southern England.1
Fortunately, Schwerdtfeger had been cataloguing and analysing weather trends of the preceding thirty years and was able to find some patterns that conformed, in part, to the requirements demanded.2 With due caution, on 11 December he predicted three-to-four days of calm succeeded by poorer weather and fog commencing on 15 December. This corresponded with Recknagel’s prediction of two weeks of rain, fog and heavy snow, beginning on 16 December, based on the reports of Dobratz, his fellow submariners and the Spitzbergen weather station.3 Both Schwerdtfeger and Schuster were promoted one grade for their services, while Crista Schroeder, one of Hitler’s secretaries, recalled that his young ‘weather prophet’ Schwerdtfeger, who had predicted the period of fog before the offensive began, ‘received a gold watch in gratitude for his correct forecast’.4
Bletchley Park analysts saw a sudden spike in the number of U-boats recording weather and in the quantity of meteorological reports transmitted, but were clueless, until the great attack began, as to why. On 19 December, Kapitän Dobratz in U-1232 and three other U-boat commanders were radioed thanks from Koralle in Bernau, ‘Your recent [weather] reports contributed decisively to determining the beginning of our great offensive in the west on 16 December.’5
‘Weather was a weapon the German army used with success, especially in the Ardennes offensive,’ mused Rundstedt in a post-war debrief. Eisenhower would observe later that ‘as long as the weather kept our planes on the ground it would be an ally of the enemy, worth many additional divisions’.6
Herbstnebel was on!
In planning, Hitler and OKW seemed to have thought of everything: the weather; paratroopers; SS commandos and, of course, the three attacking armies. They had also come up with another – often overlooked – aspect of attacking and distracting the Allies, this time on the soil of England. It was known that many German military prisoners were screened initially for their political sympathies at Camp 23 (Le Marchant Barracks in Devizes, Wiltshire), where they would be graded by a coloured patch sewn on to their uniform. White denoted indifference to National Socialism. Grey meant that the prisoner, although not an ardent Nazi, had no strong feelings either way; dedicated fanatics and true believers wore a black patch, were labelled Category ‘A’, and posted elsewhere to ‘black’ camps in remote parts of the United Kingdom.
The screening process was hurried during the autumn of 1944 due to the large volume of prisoners arriving in Britain, which led to some ‘blacks’ being mixed in camps with the moderates. In early December 1944 the Category ‘A’ Waffen-SS, U-boat and Fallschirmjäger captives housed temporarily at Devizes received orders by means of coded letters from ‘relatives’ in the Reich. They were to break out in support of the Ardennes offensive, seize weapons including tanks from a nearby army base and march on London.
The plan was betrayed by an anti-Nazi captive, Feldwebel Wolfgang Rosterg, and the ringleaders immediately despatched as far away as possible, to Camp 21 at Cultybraggan, deep in the central highlands of Scotland. Because of an administrative error, Rosterg and another moderate, Unteroffizier Gerhard Rettig, were sent there too – where the Category ‘A’ Germans retaliated. Rosterg was hanged in the camp latrine and Rettig beaten to death, though seven of their murderers were later executed in north London’s Pentonville Prison. The innovative rebellion caused much concern in wartime Britain, where around 600 camps containing 250,000 German prisoners of war were guarded by the merest fraction of that number, often men from the Pioneer Corps or Polish refugees in uniform.
Generally the German captives were an extremely well-behaved lot, for whom British hospitality represented a consistently higher standard of living than their comrades enjoyed in the Third Reich. The same was true of the far greater numbers shipped to the United States and Canada. In all three countries, prisoners worked on the land and befriended local families, while very few indeed proved to be diehard members of the ‘escapers club’ more frequently seen in the Allied prisoner of war camps of Germany and Poland. Astonishingly, in Britain those captives who undertook farm labouring, construction work or cleared bomb damage were actually paid at current union rates, of between three and six shillings for a forty-eight-hour week.7
The march on London was a brilliant concept, if illegal under international law, which came to nothing. Today’s military minds would call it asymmetric warfare.