Are there any resources about the inspirations of Miyazaki in making Howl's Moving Castle? I am doing an analysis of Miyazaki's films and am starting with Howl's Moving Castle. I have lots of information about the movie, but am having a hard time finding information regarding the inspirations for the film. I am aware that the film is an adaptation of Jones's novel in 1986 and went on to be one of the highest grossing film in Japan. But are there more interesting facts regarding the inspirations/history for the film that anyone can provide me?

Edit: I am looking to see if anyone knows of what the inspirations were for Miyazaki to direct the film. Or going back a step, the inspirations of the author to write the novel.
I don't think this book has anything about Howl's Moving Castle in particular, but Starting Point: 1979 - 1996, written by Hayao Miyazaki himself, and translated by Beth Cary and Frederik L. Schodt, is a 500 page treasure trove of interviews and other works regarding Miyazaki's thoughts and inspirations on his films. I purchased this book many years ago and only read a portion of it, so I can't really attest to how much this will help, but it's a good starting point for your research on his other films (pun may or may not be intended).

EDIT: Upon further research on Amazon, I discovered that he has another book called Turning Point, 1997 - 2008 along the same series, which does seem to contain information on Howl's Moving Castle. You might want to take a look into this.