and by 6 October the entire country of Poland was subdued. In 1940, Blumentritt—as the Operations Officer of Army Group A (again under von Rundstedt)—took part in the planning (with von Manstein and Henning von Tresckow) and execution of the invasion of France. The plan he helped develop was called Sichelschnitt or "Sickle Cut", and was later referred to as the Manstein Plan. The subsequent unmitigated success of the German Blitzkrieg in France and the complete collapse of the French defense shocked even the Germans. However, as the German army closed in on complete victory, Blumentritt and Rundstedt ignored conflicting orders from the OKH to advance on the British and French position at Dunkirk, and instead followed Adolf Hitler′s order to halt for three days, consequently allowing the evacuation of the British Forces. Immediately after the German occupation of France, Rundstedt, Blumentritt, and others were tasked with preparing for the invasion of Great Britain. This plan, as handed down from high command, was designated Operation Sea Lion. Blumentritt helped with the details of the plan, and several exercises were carried out in preparation for it, but he never believed that it was a serious option, or that Hitler intended to carry it out. He said that at the end of July or August "...Field-Marshal von Rundstedt was in Berlin, and Hitler stated quite clearly to him that he did not intend to carry out Sea Lion," and further, "By the end of September it was clear that the invasion of England was off." In 1941, Blumentritt, under General Günther von Kluge, was made Chief of Staff of the 4th Army and promoted to general. Despite his initial opposition he later was involved in the planning and operation of the German invasion of the Soviet Union. On 18 April 1941, Blumentritt wrote: Maybe the Russians really intend to stand and fight the Germans between the western border and the Dnieper, a move which would be desirable...Even the Imperial Army was no match for the German command, and the Russian commanders today are at an even greater disadvantage. The shortcomings of the middle ranks are even greater...The effects of German weapons, whose prestige has increased with the campaign against Yugoslavia, will soon be felt! There will be fourteen days of heavy fighting. Hopefully, by then we shall have made it. In another memo, Blumentritt wrote: On warfare and the inner value of