Mechelen incident
The incident was caused by an error by the German aviator Major Erich Hoenmanns, the fifty-two-year-old base commander of Loddenheide airfield, near Münster.
On the morning of 10 January 1940, he had been flying a Messerschmitt Bf 108 Taifun, an aircraft used for reconnaissance, liaison, and other miscellaneous roles, from Loddenheide to Cologne when he lost his way; extensive low fogbanks obscured his view of the landscape.
However, having already crossed over the frozen and indistinguishable Rhine at the moment he changed direction, he left German territory flying all the way to the River Meuse, the border in this area between Belgium and the Netherlands, and ended up circling Vucht.
Usually, Reinberger would have had to make the tedious trip by train, but Hoenmanns needed some extra flying hours anyway and wanted to take his laundry to his wife in Cologne.
Hoenmanns was unaware that Reinberger would be carrying documents related to the German plan for the attack on The Netherlands and Belgium, which on the day of the flight was decreed by Hitler to take place a week later on 17 January.
On hearing this, Reinberger panicked and rushed back to the plane to secure his yellow pigskin briefcase, crying that he had secret documents that he must destroy immediately.
As a diversion once more, Hoenmanns asked the Belgian soldiers to let him use the toilet; Reinberger then tried to stuff the papers into a burning stove nearby.
In the Oberkommando der Wehrmacht, the German armed forces high command, it caused general consternation, as it was soon deduced that Reinberger must have had papers revealing parts of the attack plan with him.
On 12 January, the day of the attachés' first meeting with Reinberger and Hoenmanns, General Alfred Jodl, the Wehrmacht's Chief of Operations, gave Hitler a worrying assessment of what the Belgians might have learned from it.
"[3] The second part of the plan was to let Reinberger and Hoenmanns meet the German Air and Army Attachés, Wenninger and Rabe von Pappenheim, while their conversations were secretly recorded.
After the meeting at the police station, Vicco von Bülow-Schwante, Germany's ambassador to Belgium, telegraphed his superiors: 'Major Reinberger has confirmed that he burnt the documents except for some pieces which are the size of the palm of his hand.
"[5] During 10 January the Belgians still doubted the authenticity of the documents, which had been quickly translated by the Deuxième Section (military intelligence) of the general staff in Brussels.
That afternoon King Leopold III of Belgium decided to inform his own Minister of Defence, General Henri Denis, and the French supreme commander, Maurice Gamelin.
Lord Gort, the commander of the British Expeditionary Force, was also warned, and Leopold personally telephoned Princess Juliana of the Netherlands and Grand Duchess Charlotte of Luxembourg, telling the former "Be careful, the weather is dangerous", and the latter "Beware of the flu", both predetermined code phrases indicating the Belgians considered a German attack to be imminent.
On the morning of 12 January, Gamelin held a meeting with the highest French operational army commanders and the Chief of Military Intelligence Colonel Louis Rivet.
Rivet was sceptical of the warning but Gamelin considered that, even if it were a false alarm, this would be an excellent opportunity to pressure the Belgians into allowing a French advance into their country.
If this invasion scare would make the Belgians take the side of France and Britain, this awkward problem would be partially solved and strategically vital ground from which to launch the attack effortlessly gained.
In the evening of 13 January, a message from Colonel Georges Goethals, Belgium's Military Attaché in Berlin, included these words: "Were there tactical orders or parts of them on the Malines[8] plane?
[11] Van den Bergen, who had secretly promised Gamelin to bring Belgium in on the allied side,[12] then decided to broadcast (on a popular current affairs radio programme) that night at about 22:30, an immediate recall to their units of all the 80,000 Belgian soldiers on leave.
Although Queen Wilhelmina of the Netherlands and her government were alarmed by the Belgian warning, Dutch supreme commander Izaak H. Reijnders was sceptical of the information.
When the Belgian military attaché in The Hague, Lieutenant-Colonel Pierre Diepenrijckx, handed him a personal memorandum from Van Overstraeten on 12 January, he responded "Do you believe in these messages yourself?
On the morning of 14 January, he had sent a message to Winston Churchill, then First Lord of the Admiralty, via Admiral Sir Roger Keyes asking for certain guarantees.
[21] Édouard Daladier, the French Président du Conseil in January 1940, quickly told the British Government that, as far as France was concerned, the guarantees could be given.
So the French believed that the Belgians would receive a satisfactory response from the British Government in relation to the guarantees, and would then immediately invite the Allied Armies to march in.
Gamelin ordered that the Allied troops under his control during the night of 14–15 January should make their approach march to the Franco-Belgian border so that they would be ready to enter at a moment's notice.
Alarmed by the order, Georges worried that the decision was irreversible and would set a series of events in motion that would make a German invasion inevitable at a moment when the French army and airforce had not yet completed their rearmament.
Three hours later Daladier, prompted by the desperate Gamelin who insisted that the premier would make the Belgian government "face up to its responsibilities", told Pol le Tellier, Belgium's Ambassador in Paris, that unless the French had an invitation to enter Belgium by 8 p.m. that evening, they would not only withdraw all British and French troops from the border but would also refuse to carry out similar manoeuvres during further alerts until after the Germans had invaded.
The King and Van Overstraeten, both staunch neutralists, hoped a diplomatic solution could be reached to end the war and had no intention of involving their country unless it were absolutely necessary.
On 15 January road conditions were so poor due to the snowfall and the weather prospects so bleak that Jodl advised Hitler to call the invasion off indefinitely.
[31] His stance has been explained as an inability to believe that the very traditional German High Command would resort to innovative strategies, let alone to the even more novel "Blitzkrieg" tactics needed to make them work; any large concentration of forces being supplied through the poor road network in the Ardennes would have had to act very quickly.
