Less a campaign than the very tiniest start of one wrapped in a large body of world-building (calenders, cults, etc) material the GM might likely draw on in the course of running it. Sometimes this material feels like stuff cut from the main rulebook for length, but what it all does well is make clear that the setting isn't Dungeons and Dragons at all. No, this is a far more grim and grimey world. Dirty in the ways the real world likely was in late Renaissance times with all the dark magic our ancestors believed in alive and dangerous.