As a traditional soldier, Blaskowitz kept firm control on the men under his command in their dealings with civilians and was opposed to Army participation in war crimes by the SS and
Einsatzgruppen. He handed out death sentences to members of the SS for crimes against the civilian population, which were rescinded by Hitler.
Between November 1939 and February 1940 he wrote several memoranda to higher military officials, in which he detailed SS atrocities in Poland, their negative effects on Wehrmacht soldiers and the insolent attitude of the SS toward the army. However, his protests failed to produce results, and merely earned him the enmity of
Hitler,
Hans Frank,
Reinhard Heydrich and
Heinrich Himmler, while Chief of Staff
Alfred Joel dismissed them as naive and "uncalled for".
Commander-in-Chief
Walther von Brauchitsch forwarded Blaskowitz's first memorandum to Hitler on 18 November, who launched a tirade against Blaskowitz, denouncing his concerns about due process as "childish" and poured scorn on his "Salvation Army attitude." In February 1940, Blaskowitz prepared a list of 33 complaints against the SS. Among his complaints were strip searches and rape of Jewish women, a whipping orgy in
Nasielsk affecting 1,600 Jews, and a clear case of
race mixing committed by a junior SS officer. Blaskowitz concluded that "It is a mistake to massacre some 10,000 Jews and Poles, as is being done at present; for—so far as the mass of the population is concerned—this will not eradicate the idea of a Polish state, nor will the Jews be exterminated.” Blaskowitz was relieved of his command on 29 May 1940.
In May 1944, following the appointment of
Gerd von Rundstedt as Commander-in-Chief in the West, Blaskowitz was appointed the head of
Army Group G. This comparatively small command, consisting of the
1st Army and the
19th Army, was given the task of defending southern France from the imminent Allied invasion. When in Normandy, he managed to convince Field Marshal
Erwin Rommel that the "rumours" Rommel had heard about atrocities on the Eastern Front were actually true.
https://en.m.wikipedia.org/wiki/Johannes_Blaskowitz