In preparation for the invasion of France, Manstein devised an innovative operation—later known as the Sichelschnitt ("sickle cut")—that called for an attack through the woods of the Ardennes and a rapid drive to the English Channel, thus cutting off the French and Allied armies in Belgium and Flanders. Attaining the rank of general at the end of the campaign, he was active in the invasion of the Soviet Union in June 1941. He led the Axis forces in the siege of Sevastopol and the Battle of the Kerch Peninsula, and was promoted to field marshal on 1 July 1942, after which he participated in the siege of Leningrad. He was one of the primary commanders at the Battle of Kursk (July–August 1943). His ongoing disagreements with Hitler over the conduct of the war led to his dismissal in March 1944. He never obtained another command and was taken prisoner by the British in August 1945, several months after Germany's defeat.
Manstein gave testimony at the main Nuremberg trials of war criminals in August 1946, and prepared a paper that, along with his later memoirs, helped cultivate the myth of the clean Wehrmacht—the myth that the German armed forces were not culpable for the atrocities of the Holocaust. In 1949 he was tried in Hamburg for war crimes and was convicted on nine of seventeen counts, including the poor treatment of prisoners of war and failing to protect civilian lives in his sphere of operations.
If Paulus's army had capitulated before the end, the Russians would have had the advantage of withdrawing forces against Paulus and against the southern front, where I had only two Romanian armies. Therefore, the resistance of the Sixth German Army, even to the death of the last man, was necessary.
To Leon Goldensohn (14 June 1946). Quoted in The Nuremberg Interviews - by Leon Goldensohn, Robert Gellately - History - 2004
I tried at that time to relieve the Sixth Army, of which I was supreme commander, above Paulus, by counterattacks - but it was not possible. I gave the order finally for the Sixth Army to break out, but then Paulus said it was too late and not possible. Hitler did not want the Sixth Army to break out at any time, but to fight to the last man. I believe that Hitler said if the Sixth Army tried to break out, it would be their death.
To Leon Goldensohn (14 June 1946). Quoted in The Nuremberg Interviews - by Leon Goldensohn, Robert Gellately - History - 2004
The will for victory which gives a commander the strength to see a grave crisis through is something very different from Hitler's will, which in the last analysis stemmed from a belief in his own 'mission'. Such a belief makes a man impervious to reason and leads him to think that his own will can operate even beyond the limits of hard reality - whether these consist in the presence of far superior enemy forces, in the conditions of space and time, or merely in the fact that the enemy also happens to have a will of his own.
Describing Mission Command, Lost Victories, The Winter Campaign In South Russia
But it is a well-known maxim of war that whoever tries to hold on to everything at once, finishes up by holding nothing at all.
Lost Victories, The Winter Campaign In South Russia
He was not only the most brilliant strategist of all our generals, but he had a good political sense. A man of that quality was too difficult for Hitler to swallow for long. At conferences Manstein often differed from Hitler, in front of others, and would go so far as to declare that some of the ideas which Hitler put forward were nonsense.
The general verdict among the German generals I interrogated in 1945 was that Field-Marshal von Manstein had proved the ablest commander in their Army, and the man they had most desired to become its Commander-in-Chief. It is very clear that he had a superb sense of operational possibilities and equal mastery in the conduct of operations, together with a greater grasp of the potentialities of mechanized forces than any other commander who had not been trained in the tank arm. In sum, he had military genius.
Manstein despised Göring and loathed Himmler. To his most trusted colleagues he admitted to Jewish antecedents. He could also be scathing about Hitler. As a joke, his dachshund Knirps had been trained to raise his paw in salute on the command "Heil Hitler". On the other hand, his wife was a great admirer of Hitler, and more importantly, Manstein, as already mentioned, had even issued that order to his troops mentioning "the necessity of hard measures against Jewry"
He had utter disdain for the Nazis and had no time for their racial purity agenda.
Nuremberg Trial transcripts
I asked the Field Marshal von Manstein if he would take part in the actions against Hitler. Manstein was sitting in a chair and reading the Bible. Quick, almost embarrassed, he put it aside and covered it with some papers.