So did I. They are grim, but that's kind of the point -- it's a reflection on the tragedy of history and how people end up making the same mistakes over and over again.
When I said "grim, hard slog" I was referring to the experience of reading them, not the nature of their content. The experience of reading anything that monotonous would be pretty grim, even with a brighter theme and a happy ending. Of course, ymmv, etc.