The Book of Swords Series is collectively a science fiction/fantasy novel series written by Fred Saberhagen. Its central theme revolves around twelve magical Swords forged by the gods, each endowed with a particular power or gift, and how various people acquire and use them. The series spans several decades and features dozens of characters.
The Swords of Power are created by the god Vulcan. Each has its own unique magical ability, and they are powerful enough to affect the mythological gods that exist within the series. The plot of the entire series revolves around the finding, acquiring, stealing, using, and eventual destroying of the Swords for purposes good or evil.
The Book of Swords series blends science fiction and fantasy to create unique takes on the staples of both genres. The back story to the Swords universe is explained in Saberhagen's Empire of the East series.
The books are set far into the future, although this is not immediately obvious to the reader. Approximately 50,000 years before the story, sometime during our third millennium, mankind is almost driven to extinction by a global apocalypse. This is explained as being brought on by a nuclear World War prior to the events in Empire of the East. An intelligent super-computer, ARDNEH, part of a former American nuclear response system, initiated a physical change to the structure of the world. Unintentionally combined with a similar system on the other side of the world, this change negated the effects of atomic weaponry and most other forms of high technology, and introduced other side-effects, such as the creation of magic, gods, and demons. ARDNEH then continued to stabilize and sustain humanity through the ensuing Dark Ages. ARDNEH was destroyed millennia before the events of the series, as chronicled in Saberhagen's Empire of the East series. By the time the events recorded in The Books of the Swords occur, ARDNEH has passed into legend, worshiped as a benevolent god.