stepping back in time...
http://www.danielpipes.org/article/448
“Military Slaves: A Uniquely Muslim Phenomenon”
by Daniel Pipes
The Arming of Slaves from the Ancient World to the American Civil War
November 16-18, 2000
The tradition of slave soldiers (called Mamluks) culminated in the ascension of Baibars of the ‘Warriors of the White Sands’ to Sultan of Egypt. He was the Sultan who “A Thousand and One Arabian Knights” is based upon. He was a one eyed guy from a cataract (his other eye was blue), and like Odin, would often wander among his people incognito. He drove the Crusaders out of the Levant.
After Baibars the idea of a highly armed “slave” army lost much of its appeal.