I am reading the above referenced book which is a memoir written some years after the campaign by Jakob Walter. Walter was a soldier from Württemberg which was one of the states of the Confederation of the Rhine. He participated in a few of Napoleon’s campaigns including the invasion of Russia.
One of the things I was surprised to find out in doing the research for my book was that the troops began to suffer from lack of provisions before they even entered Russia. Walter tells about how his regiment plundered one Polish village and found the food the villagers had hidden. The inhabitants complained and the troops were brought under control with the threat of death.
Another incident along a different line is the appearance of swarms of bugs. It was May as they passed through Poland and “…the air swarmed with May bugs so amazingly that it was hard to keep your eyes open in the evening. The bugs were so very thick that they darkened the atmosphere, and everyone was busy shaking them out of his face and hair.”