From the Introduction:
1806 The Treaty of Pressburg was a disaster, but no one was aware of how much of a disaster. Things were kept away from our reality by the presence of the Holy Roman Empire; many of the lives lost that were instrumental in keeping the world hidden. There are things of darkness, madness and evil, which feasted on suffering, pain, and the Emperor Napoleon, brought many of these with him. The blood shed at Austerlitz lit the fuse to blow open the portals to our world.
For centuries, certain priests of the Holy Roman Empire performed a daily ritual to keep our lands safe. However, an errant artillery shell killed them in the middle of this ritual. The sudden brutality of their deaths left it impossible to pass this knowledge on. A week after the death of these priests, the first cracks in the veil begin to manifest.
1808 Austerlitz becomes a nightmare land, those living in the area change. Malformed, demonic shapes, the dead rise to walk once more, other creatures not of our world spew forth in more terrifying forms, the lands became despoiled and changing. This was only the first, they engaged Napoleons armies in battle, and few survived. The sky burned and entire battle groups disappeared in these hellish lands. Many cities of the once great Holy Roman Empire are quickly swallowed up by the blight.
1809 Emperor Napoleon set aside pride and allied with other powers to drive these demonic forces away. However, many of these factions blamed Napoleon for the current state of affairs. They are not far wrong. Nevertheless, they attacked…and failed. The demon armies grow in strength
1810 You are a member of one of the mockingly self-named Hell Companies. The world has gone mad... and you need to survive, and stay sane. Face to face with demons will test your will and your courage, but first you must reach Rome, find the library at the Quirinal Palace, and locate the tomes needed to seal the rifts. Many have tried, none have returned.