These books meet not only the criteria for "fanfic" but also for "real person fic!" How derivative can you get and still be considered a "real" writer????

Yeah. I must admit that Real Person fanfic is one of my personal "not going there" areas. And yet, I love "biopic" novels or movies. I do think that it's not just whether the persons do or have existed or not - for me it's about what the purpose of the story is. If it's just an excuse to write porn or schmaltzy romance, I'm not interested. If it's a serious attempt to understand the motivations, thoughts and actions of a historical figure under certain circumstances, then I'm often fascinated.