Last Sword of Power by David Gemmell
This fantasy novel tells the story of the quest to maintain the vital balance of light and dark and good and evil. As a new dark age looms over Roman Britain, the soul of Uther Pendragon is chained in Hell and his realm is under threat. But a man called Revelation arrives with a message of hope. The other novels by David Gemmel are "Legend", "Beyond the Gate", "Waylander", "Wolf in Shadow" and "Ghostking".