Who is this Prester John character, anyway?

Factual Questions
1

This has always nagged at me, that I don’t know who he was. A brief but frustrating search online turned up sites that variously claimed:

–he’s a myth
–he’s an actual guy who had an African empire in Ancient times
–he’s an actual African guy who had an African empire during the renaissance
–he’s a white guy who had an African empire during the renaissance
–“prester” is actually a title, not a name, so there are many of these people through out history
–while based on an actual person, the stories which have sprung up are so far-removed from any facts that we can safely consider them all to be mythical (like King Arthur)

So help me out here, what is the REAL straight dope???

2

I thought Prester John had his kingdon in central Asia.

3

This article covers it pretty well.

4

I’ll give you the collection I was building up while he answered, too:

http://www.newadvent.org/cathen/12400b.htm
http://geography.about.com/science/geography/library/weekly/aa081098.htm

http://www.fordham.edu/halsall/source/mandeville.html
http://www.philaprintshop.com/presjohn.html

Synopsis:

The original legend placed Prester John’s kingdom in Asia, later versions in North Africa.

The accounts are mythical. An actual person at the core of the legend seems doubtful, given the origins (the Crusades).

Prester is indeed a title, derived from “Presbyter”.

I’m kind of curious about it myself, because I have the legend in the back of my mind as raw material for writing a contemporary fantasy. Celtic legend has been over-mined. H. Warner Munn used it, but off the top of my head, I can’t think who else. I’m sure somebody is now going to provide me with a list.

Robert Silverberg wrote a book on the myth “The Realm of Prester John”, which I will order if I get serious about the project.