The sword and the chain : a fantasy novel

"Once they had been college students playing a roleplaying game. Then, they found that somehow they had become their characters, transported to the Other Side. Now they have chosen the fantasy world for their own, and are fighting for its freedom."@en
"Karl, Andrea, Ahira, Walter, and Lou. Who are all from present day America. They have been transported to the past, a mystic world in which magic, not science prevails. Bound by their pledge to the Healing Hand society, they cannot return home until they give freedom to each and every person in the world of the past. After intercepting a few slaver caravans, Karl, Andrea, Ahira, Walter, Lou, and their new recruits (the slaves they freed) settle down in a remote valley. Because all of them are wanted criminals or slaves, the valley that no one knows about is the perfect place to settle down. Now, it becomes a race against time to make their valley civilization grow to a sufficient size (so they can protect themselves) before they are discovered."@en