There is a true story?

[Googolplex]

The old Kingdom of Prussia between 17th and 19th century was in northern middle europe. I heared about a Brennenburg Castle in reality. The builder was Alexander of Brennenburg.
And in the castle were some crimes, but nobody really knows about it. There was only one noble man named "Wilhelm" who leave some documents about that crimes.
Where is this castle now?

Is it only a fantasy story for Amnesia, or have it all a true story?

If I google about Alexander of Brennenburg, I can only find it linked to Amnesia.

Here is a text in the remember.pdf from Frictional Games:

Altstadt has never seen much crime, but there was a dark period
spanning from the early winter of 1702 until late summer of 1704.
During these years no less than 39 men were arrested and locked up
in castle Brennenburg’s dungeons. In most cases the criminal’s family
would be banished from the land, effectively cutting the already
dwindling population of Altstadt with 86 souls. The magistrate’s
office has almost no records detailing these crimes, as most arrests
were handled by an unknown nobleman named Wilhelm.

Klaas Gottschall
University of Königsberg


Is it also a real story?

[Oscar House]

Doubt it. Even though some of the places actually exist (Königsberg, Altstadt), it doesn't mean there's a true story behind it.

[Arvuti]

I really doubt that it's a true story, frictional probably did take some inspiration from history. Agrippa was actually based off a real life figure (http://en.wikipedia.org/wiki/Heinrich_Cornelius_Agrippa).

[Kein]

It is mixed, juts like H. P. L. stories.

[LuckyBlackCatXIII]

As said there's a lot of places, events and people that are used in the game, such as Sir William Smith (who did really die in 1839 [but not in the right month that the game states]), the Order of the Black Eagle and the 'Occupation' of Napoleon that Alexander states in one of his memory cylinders, but they're most likely not true. I have to give props to Frictional though, they added a lot of historical figures and events to make this seem almost plausible.

[pompano]

I doubt this is a true story lol.