Darren Shan's The Thin Executioner

Shan creates an entire world with various cultures, religions and villains in his archetypal tale, The Thin Executioner.  Inspired by the country of Jordan, Jebel Rum sets out on a quest to gain superhuman strength and get his honor back.  Throughout his journey, our young hero learns to believe in himself and consequently learns what it is to be kind and humble.

In the dedication page, the author thanks the country of Jordan for his plot and setting inspiration.  What I want to know is WHEN does this story take place?  Some of the practices of Um Aineh are rather primitive and barbaric, but the weapons are extremely advanced and futuristic.  Whenever a character is introduced, the author is careful to mention the color of the character's skin, and his religious beliefs.  Ironically, characters with monotheistic beliefs are light skinned and enslaved.  Polytheistic characters are dark skinned, and rule the world.  Jebel Rum is worships many gods and dark skinned, whereas his enslaved companion, Tel Hasani, is light skinned and worships one god.  When Tel Hasani speaks of his religious beliefs, they sound much like Christian doctrine.  Could the setting of the story be from a distant time in the future?