SHORTLY AFTER DAWN on the fine spring day of May 10, 1940, the ambassador of Belgium and the minister of the Netherlands in Berlin were summoned to the Wilhelmstrasse and informed by Ribbentrop that German troops were entering their countries to safeguard their neutrality against an imminent attack by the Anglo–French armies—the same shabby excuse that had been made just a month before with Denmark and Norway. A formal German ultimatum called upon the two governments to see to it that no resistance was offered. If it were, it would be crushed by all means and the responsibility for the bloodshed would “be borne exclusively by the Royal Belgian and the Royal Netherlands Government.”
In Brussels and The Hague, as previously in Copenhagen and Oslo, the German envoys made their way to the respective foreign offices with similar messages. Ironically enough, the bearer of the ultimatum in The Hague was Count Julius von Zech-Burkersroda, the German minister, who was a son-in-law of Bethmann-Hollweg, the Kaiser’s Chancellor, who in 1914 had publicly called Germany’s guarantee of Belgian neutrality, which the Hohenzollern Reich had just violated, “a scrap of paper.”
At the Foreign Ministry in Brussels, while German bombers roared overhead and the explosion of their bombs on nearby airfields rattled the windows, Buelow-Schwante, the German ambassador, started to take a paper from his pocket as he entered the Foreign Minister’s office. Paul-Henri Spaak stopped him.
“I beg your pardon, Mr. Ambassador. I will speak first.”
The German Army [Spaak said, not attempting to hold back his feeling of outrage] has just attacked our country. This is the second time in twenty-five years that Germany has committed a criminal aggression against a neutral and loyal Belgium. What has happened is perhaps even more odious than the aggression of 1914. No ultimatum, no note, no protest of any kind has ever been placed before the Belgian Government. It is through the attack itself that Belgium has learned that Germany has violated the undertakings given by her … The German Reich will be held responsible by history. Belgium is resolved to defend herself.
The unhappy German diplomat then began to read the formal German ultimatum, but Spaak cut him short. “Hand me the document,” he said. “I should like to spare you so painful a task.”1
The Third Reich had given the two small Low Countries guarantees of their neutrality almost without number. The independence and neutrality of Belgium had been guaranteed “perpetually” by the five great European powers in 1839, a pact that was observed for seventy-five years until Germany broke it in 1914. The Weimar Republic had promised never to take up arms against Belgium, and Hitler, after he came to power, continually reaffirmed that policy and gave similar assurances to the Netherlands. On January 30, 1937, after he had repudiated the Locarno Treaty, the Nazi Chancellor publicly proclaimed:
The German Government has further given the assurance to Belgium and Holland that it is prepared to recognize and to guarantee the inviolability and neutrality of these territories.
Frightened by the remilitarization of the Third Reich and its reoccupation of the Rhineland in the spring of 1936, Belgium, which wisely had abandoned neutrality after 1918, again sought refuge in it. On April 24, 1937, Britain and France released her from the obligations of Locarno and on October 13 of that year Germany officially and solemnly confirmed
its determination that in no circumstances will it impair the inviolability and integrity [of Belgium] and that it will at all times respect Belgian territory … and [be] prepared to assist Belgium should she be subjected to an attack …
From that day on there is a familiar counterpoint in Hitler’s solemn public assurances to the Low Countries and his private admonitions to his generals. On August 24, 1938, in regard to one of the papers drawn up for him for Case Green, the plan for the attack on Czechoslovakia, he spoke of the “extraordinary advantage” to Germany if Belgium and Holland were occupied and asked the Army’s opinion “as to the conditions under which an occupation of this area could be carried out and how long it would take.” On April 28, 1939, in his reply to Roosevelt, Hitler again stressed the “binding declarations” which he had given to the Netherlands and Belgium, among others. Less than a month later, on May 23, the Fuehrer, as has been noted, was telling his generals that “the Dutch and Belgian air bases must be occupied by armed force … with lightning speed. Declarations of neutrality must be ignored.”
He had not yet started his war, but his plans were ready. On August 22, a week before he launched the war by attacking Poland, he conferred with his generals about the “possibility” of violating Dutch and Belgian neutrality. “England and France,” he said, “will not violate the neutrality of these countries.” Four days later, on August 26, he ordered his envoys in Brussels and The Hague to inform the respective governments that in the event of an outbreak of war “Germany will in no circumstances impair the inviolability of Belgium and Holland,” an assurance which he repeated publicly on October 6, after the conclusion of the Polish campaign. The very next day, October 7, General von Brauchitsch advised his army group commanders, at Hitler’s prompting,
to make all preparations for immediate invasion of Dutch and Belgian territory, if the political situation so demands.2
Two days later, on October 9, in Directive No. 6, Hitler ordered:
Preparations are to be made for an attacking operation … through Luxembourg, Belgium and Holland. This attack must be carried out as soon and as forcefully as possible … The object of this attack is to acquire as great an area of Holland, Belgium and northern France as possible.3
The Belgians and Dutch, of course, were not privy to Hitler’s secret orders. Nevertheless they did receive warnings of what was in store for them. A number of them have already been noted: Colonel Oster, one of the anti-Nazi conspirators, warned the Dutch and Belgian military attachés in Berlin on November 5 to expect the German attack on November 12, which was then the target date. At the end of October Goerdeler, another one of the conspirators, had gone to Brussels at the instigation of Weizsaecker, to warn the Belgians of an imminent attack. And shortly after the New Year, on January 10, 1940, Hitler’s plans for the offensive in the West had fallen into the hands of the Belgians when an officer carrying them had made a forced landing in Belgium.*
By that time the Dutch and Belgian general staffs knew from their own border intelligence that the Germans were concentrating some fifty divisions on their frontiers. They also had the benefit of an unusual source of information in the German capital. This “source” was Colonel G. J. Sas, the Netherland’s military attaché in Berlin. Sas was a close personal friend of Colonel Oster and often dined with him at the latter’s home in the secluded suburb of Zehlendorf—a practice facilitated, once the war broke out, by the blackout, whose cover enabled a number of persons in Berlin at that time, German and foreign, to get about on various subversive missions without much fear of detection. It was Sas whom Oster tipped off early in November about the German onslaught then set for November 12, and he gave the attaché a new warning in January. The fact that neither attack came off somewhat lessened the credibility of Sas in The Hague and in Brussels, where the fact that Hitler had actually set dates for his aggression and then postponed them naturally was not known. However the ten days’ warning that Sas got through Oster of the invasion of Norwayand Denmark and his prediction of the exact date seems to have restored his prestige at home.
On May 3, Oster told Sas flatly that the German attack in the West through the Netherlands and Belgium would begin on May 10, and the military attaché promptly informed his government. The next day The Hague received confirmation of this from its envoy at the Vatican. The Dutch immediately passed the word along to the Belgians. May 5 was a Sunday and as the week began to unfold it became pretty obvious to all of us in Berlin that the blow in the West would fall within a few days. Tension mounted in the capital. By May 8 I was cabling my New York office to hold one of our correspondents in Amsterdam instead of shipping him off to Norway, where the war had ended anyway, and that evening the military censors allowed me to hint in my broadcast that there would soon be action in the West, including Holland and Belgium.
On the evening of May 9 Oster and Sas dined together for what would prove the last time. The German officer confirmed that the final order had been given to launch the attack in the West at dawn the next day. Just to make sure that there were no last-minute changes Oster dropped by OKW headquarters in the Bendlerstrasse after dinner. There had been no changes. “The swine has gone to the Western front,” Oster told Sas. The “swine” was Hitler. Sas informed the Belgian military attaché and then went to his own legation and put through a call to The Hague. A special code for this moment already had been arranged and Sas spoke some seemingly innocuous words which conveyed the message “Tomorrow, at dawn. Hold tight!”4
Strangely enough, the two Big Powers in the West, Britain and France, were caught napping. Their general staffs discounted the alarming reports from Brussels and The Hague. London itself was preoccupied with a three-day cabinet crisis which was resolved only on the evening of May 10 by the replacement of Chamberlain by Churchill as Prime Minister. The first the French and British headquarters heard of the German onslaught was when the peace of the spring predawn was broken by the roar of German bombers and the screech of Stuka dive bombers overhead, followed shortly afterward, as daylight broke, by frantic appeals for help from the Dutch and Belgian governments which had held the Allies at arm’s length for eight months instead of concerting with them for a common defense.
Nevertheless the Allied plan to meet the main German attack in Belgium went ahead for the first couple of days almost without a hitch. A great Anglo–French army rushed northeastward from the Franco–Belgian border to man the main Belgian defense line along the Dyle and Meuse rivers east of Brussels. As it happened, this was just what the German High Command wanted. This massive Allied wheeling movement played directly into its hands. Though they did not know it the Anglo–French armies sped directly into a trap that, when sprung, would soon prove to be utterly disastrous.