The Sword Of Knowledge

First of all, you should know that this is not a book by C. J. Cherryh. The Sword Of Knowledge consists of three books, published separately in 1989 and made into one volume later. All three books were allegedly co-authored by C. J. Cherryh, although it is difficult to say to what degree.

The first of the three books is A Dirge For Sabis, written by C. J. Cherryh with Leslie Fish. The stage is Sabis, swiftly falling to the hands of barbarian invaders. In Sabis, a group of craftsmen centered around a scholar named Sulun works on what perhaps is a last hope for Sabis - a cannon. Their work fails though, and the group flees - not from the barbarian hordes, but into their midst, trying to find an inconspicuous refuge where to continue their work ...

The second of the books is Wizard Spawn, by C. J. Cherryh and Nancy Asire. Many years after the fall of Sabis, Sulun and his group of scholars is just a legend, his kind all but enslaved by the long-ago-settled invaders. Duran, an alchemist by trade, is of the invading race too - but unlike others, he does not harbor hate towards the sabin race - something that makes him strange and suspicious in the eyes of his neighbors. When he gives help and shelter to an injured sabin child, his neighbors revolt ...

The third and final book is Reap The Whirlwind, by C. J. Cherryh and Mercedes Lackey. The knowledge of Sulun and his companions is not lost after all, preserved by a group of fugitive scholars and passed from generation to generation. The end seems to be coming though, as the valley inhabited by the scholars prepares to meet an onslaught of nomads ...