In High Places, Tor, 2006, is the third novel in the Crosstime Traffic series. It follows the adventures of Annette Klein, who is traveling through a world in which the Black Plague wiped out a greater percentage of the European population. As a result, Southern Europe is under Muslim rule, and Northern Europe is a relative backwater. Christianity has shifted dramatically thanks to the arrival of "God's Second Son", Henri.
On a journey from the Kingdom of Versailles to Marseille with her parents, Klein, along with a local named Jacques are captured by slavers and separated from her parents. The two are taken to another world by renegade Crosstimers who use the Crosstime technology to run a slaving world.
The novel details Klein's attempts to escape back to the world of Crosstime Traffic to reveal the illegal activities.
The premise of the Black Death hitting Europe much more heavily than in OTL, leaving it vulnerable to Islamic invasion and preventing the centuries of European domination of the world, is also taken up in:
Robert Silverberg's The Gate of Worlds[1], where a Europe decimated by the plague is conquered entirely by the Ottoman Empire, London becomes New Istanbul, Shakespeare writes his plays in Turkish, and England succeeds only in the 20th Century to become independent again - but poor and backward.
Kim Stanley Robinson's more drastic version in The Years of Rice and Salt [2] where the plague kills 99% of the Europeans and the virutally empty Europe is throughly colonized by Muslims and becomes the continent of Firanja.
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