So now that we have some background on the owners and history of the schloss you understand the context of the place.
And as any good archivist knows, "Context is everything."
I mentioned that Max spent a great deal of time and money renovating the schloss. He created the library and redid the dining room with a Venetian theme.
He also built an ampitheatre in the park so he could stage plays. Sadly the theatre was not built on solid ground and sank years ago, although there are still signs of it if you know where to look.
In fact the schloss itself was not built on solid ground, but the Archbishop took a page from the builders of Venice and used supports in the boggy ground to be the bedrock and foundation of the place. A problem with waterfront property, I guess.
After the Second World War was over the schloss was returned to Reinhardt's heirs. His widow offered the use of the place to several Harvard(yes I know...)grad students who came up with what is now referred to as the "Marshall Plan for the mind" to get former enemies to share ideas, cultures, and trust each other again. The Seminar was supposed to be a one time thing, but it was so popular with the participants that it continued on. Obviously. There have been some rather important people who attended sessions there. The Prince of Wales, and Ralph Ellison were two that I knew about from research(and cleaning) in the office. So it's very diverse.
The organization that runs the Seminar bought the place in the 1960's and so here we are. At least when it comes to ownership.
It was designated a historical place of interest by the Austrian government sometime back. From an artistic and historical standpoint you gotta love that.