For me, above all else, fantasy is highly imaginative, literally magical both to write and to read. To paraphrase Elton John, 'It's as if something unknown had come into your life.' According to Neil Gaimon, all fiction is fantasy. I would modify this slightly to say that all fiction that contains an element of magic is fantasy. Fantasy, in irs own inimitable way, while not factual must read as if it is true. To paraphrase GK Chesterton, fantasy is more than true not because it tells us that demons exist but because it tells us that demons can be defeated.
Fantasy demands a lot of imagination from both writer and reader. Epic fantasy creates a whole imaginary world, with rules of its own, yet obeying fundamental "immutable" principles. It is very popular with children and women in particular. With children often at a certain age, when they are coming to terms with the world and reading fantasy of the epic sort, it appears to involve a peculiar if interesting rites of passage.
Having written in several different fiction categories, and widely in non-fiction, I wonder if the intellectual interest of writing fantasy derives from two things: the breadth of creativity needed to create an entirely novel world, with all of its governments, rules, wars, different peoples, with their histories, etc. But also there is the subtle pleasure of writing for children. Those adults who deride fantasy fail to appreciate the importance of fiction to the child's developing mind, personality and social development. In all of these matters, there is a second consideration, which also matters a great deal - the author's intention.
When I set out to write a teenage fantasy, I might kid myself that I enter into the spirit of things with no special agenda, but inevitably a deeply personal agenda comes into it - because I am what I am, with all of my personal historical baggage, education, ethnic origins, religious attitudes, or lack of them, etc. Much of this is unconscious, but it is there, nevertheless.
As a final thought, I have long believed that a book, and most particularly a work of fiction, involves a kind of creative compact between the writer and the reader. The creativity doesn't just stop with the writer. The reader applies his or her own creativity in interpreting what, after all, are merely words on the page. That's why films are often disappointing when one has already read the book - the film-maker must apply his or her own creativity to interpret the book, and this may be quite different from that of the reader's. I read, at the front of recent novel by Neil Gaiman, the dedication, "I wrote this just for you" - and I think he hit the nail on the head. It is true in the case of every writer who ever lived. And it is true of The Snowmelt River.
Enjoy!
Frank P Ryan
P.S. See a letter from J.R.R. Tolkein to a reader