In many cases, it seems as if famous authors and others have had their entire "private correspondence" leaked somehow.
You will hear references to "Tolkien letter XYZ", etc., as if this were public information like his books, rather than private replies to individuals.
How did this happen? How did they obtain all those letters (and verify them as authentic)? Did they have no respect whatsoever for the privacy of the person writing it?
Was it actually the author himself who made a copy of each outgoing reply of his just to publish later, having deleted any sensitive information?
I don't get how this all worked.
I'm not talking about e-mails and modern day stuff, because obviously all privacy and respect is completely lost these days.