On the recommendation of Ckutalik(via this post on historical fiction for fantasy readers), I requested the book Gentlemen of the Road by Michael Chabon from the local library. A short novel or novella, it is about the adventures of a Fafhrd and Gray Mouser type in the 950s in western Asia; a fairly gripping read, I knocked it out in a couple of hours. The book itself is lovely, with two color typeset, and illustrations by Gary Gianni, who is apparently currently working on the Prince Valiant comics in papers. I recommend it for those who like quick adventure stories.
However, like all good historical fiction, the real star is the setting, which here is Western Asia, and more specifically Khazaria, a Turkic empire established in 618 AD and lasted nearly 400 years. This empire existed as a sort of third wheel to the conflicts between the Eastern Empire to the west and the early Caliphate to the south, and contains names both known to most, and strange. The empire was multi-ethnic AND multi-faith, and had both a diverse economy and significant military activity. For a while at least the country had a dual kingship, with one king responsible for administration, and the other more of a figurehead (and held as a sort of prisoner in a palace). Unusually, the rulers of the country converted to Judaism in the 8th century, possibly as a way to stand in between their Christian and Muslim neighbors.
Frankly, I think it would be perfect for a theft and insertion into a D&D game, or possibly outright use in a more historical game. The silk road and the multi-ethnic nature of the empire make it perfect for any random character to show up, and there would be plenty of raids to defeat and convoys to attack. With place names that are both familiar and foreign, and with a history merely sketched in by a few primary documents, it has much to recommend it for adventure.