Humans Discover the Chalice Dungeons and Willem Founds Byrgenwerth
After the demise of the Pthumerian civilization comes the rise of the human civilization. Judging by their clothes and technology, these humans’ timeline likely evolved in a fashion similar to our own. However, the humans in Bloodborne discovered the Ancient Pthumerian labyrinth of the Chalice Dungeons.
In the Chalice Dungeons, humans uncovered remnants of all sorts of strange ritual artifacts. The grotesque materials used for rituals included remnants of both Great Ones and Pthumerians. Humans were intrigued by their discoveries and needed to study what they had found. In order to do that, a school needed to be founded.
The most useful information in the game about where the story of Yharnam begins is probably from the NPC Alfred. When he is encountered for the first time near the entrance to Old Yharnam, he has this to say:
“Byrgenwerth is an old place of learning. And the tomb of the gods, carved out below Yharnam, should be familiar to every hunter. Well, once a group of young Byrgenwerth scholars discovered a holy medium deep within the tomb. This led to the founding of the Healing Church, and the establishment of blood healing. In this sense, everything sacred in Yharnam can be traced back to Byrgenwerth.”
Byrgenwerth is essentially a college devoted to understanding the mysteries from the artifacts that were uncovered in the old Pthumerian labyrinth of the Chalice Dungeons. The head of this college, as noted by his title of Master or Provost, was Willem.
While people are free to form their own opinions on Master Willem, the Madman Hood does give us this clue about the nature of madness:
“Truth oft resembles madness, inaccessible to the dull of mind. Those who go mad are merely thoughtful souls who failed to reach any conclusions.”
In the game, Master Willem is regarded as one of the wisest scholars to have ever lived by some, and as a fool thought to have been driven mad from his research by others.