Marco Polo & the Sleeping Beauty Put to Bed

I have finished the second novel in my October Reading List, Avram Davidson and Grania Davis' Marco Polo and the Sleeping Beauty, thus ending the Asian half of the month.  I quite enjoyed it, although it didn't make a very good choice for a Halloween reading list.  Still, it allowed me to put the two Mongol novels I had together.  It has a good deal of elements both from fairy tales and from Oriental mythology that I enjoyed. The basic set-up nothing is tried and true, and nothing you haven't heard before: Your lord has acquired an ancient map with mysterious clues, and it is your job to lead a company to find the X it leads to.  But this is one of those novels where it is not so much that the heroes accomplish anything, but more so that things happen.  The unlikely heroes are driven along by even more unlikely events.

The real question: how did Baen's Neal McPheeters get Charles Bronson to pose for Kublai Khan!?