There was a memoir I read recently, "Blood on the Snow", by a German soldier who was at the Russian front. He showed up as a greenhorn just in time to catch the last weeks of Stalingrad, and from there it was a series of withdrawls and retreats. He and his friends showed up all enthused, ready to fight for Furher and Fatherland and all that, and by the end they were completely jaded and just fighting to keep one another alive, especially as the tactical blunders mounted up and entire divisions were sacrificed whole hog.

The author took personal exception to the "sadists" in the ranks, particularly among the NCOs as they would force others to contribute, i.e. executing wounded prisoners and whatnot. In one incident, when he did a stint in Trieste--which compared to Russia, was like being on holiday--one such NCO ordered him and a friend to take a group of captured partisans into the woods and execute them. Once out of sight, they fired their rifles in the air and told the partisans to beat it. They had no problem shooting them in honest combat, but that was just too much.

This was a personal memoir and not an academic work, bear in mind. I have a feeling he was glossing over the treatment by the Germans of Russian civilians, for example.