The three major wargames closely associated with Fall Gelb were held at Koblenz, Mayen and again at Koblenz on 7 and 14 February and 21 March 1940 respectively. The games were notable for the clash between the more conservative approach of OKH Chief of Staff Franz Halder and the more strident positions of the armor forces as represented by Guderian. Halder favored a measured buildup of forces in which the panzers seized a bridgehead over the Meuse and then waited for infantry to exploit it in an operation that lasted nine or ten days. Guderian argued that the panzers and motorized forces on their own could affect a breakthrough in five days. Both Guderian and XIV Panzer Corps commander Gustav von Wietersheim declared that a conservative use of the armored and motorized formations was foolhardy and they had no confidence in the operation. For his part, Halder declared Guderian's timeframe was "senseless" at the 14 February game. Halder gradually came half-way to the panzer generals' position by 21 March game when his war diary recorded, "decision reserved in further moves after the crossing of the Meuse." The decision as to whether or not to wait for the infantry would be decided by immediate operational events.

Guderian used the wargames to outline the immediate objectives and deployments of his armored and motorized forces. Such was the brevity of the time to prepare for Fall Gelb that the 1st Panzer Division's attack orders for the breakthrough were nearly identical to the 21 March wargame. In a way, these wargames succeeded in spite of themselves. Rather than building consensus among the German high command, these exercises sowed dissension between the panzer corps and the traditional infantry officers. Halder's non-decision about the employment of infantry in the Meuse breakthrough was ideal for German Auftragstaktik (mission tactics) in that it allowed the leaders on the spot to make decisions. This level of operational improvisation carried with it enormous risks but n the case of Fall Gelb, this risk-taking paid off. The ordinance officer of 1st Panzer noted that the operation across the Meuse that "assembly, crossing, attack, and breakthrough actually came through like clockwork." However, the gap between the panzer generals and the OKH created a great deal of friction during the campaign; when Rommel was ordered to halt at 17 May, he conveniently did not receive the radio message. OKH constantly tried to walk a fine line between trying to restore a sense of operational order and not restraining the panzers' breakthrough too much. Ideally, the wargames should have minimized this friction by putting the infantry and mechanized commanders on same page, but they did not.

Sources

Frieser, Karl-Heinz. The Blitzkrieg legend: the 1940 campaign in the West. Annapolis, Md: Naval Institute Press, 2005.

Guderian, Heinz. Panzer Leader. New York: Dutton, 1952.