Whedon came up with the idea for the show after reading "The Killer Angels", a novel about the Battle of Gettysburg during the American Civil War. He wanted to follow people who had fought on the losing side of a war. He wanted to look at their lives after the war on the edges of civilization. It was meant to be the kind of drama with a lot of people trying to figure out their lives in a pioneer environment. Whedon wanted to have a show that was about when life was physical and things did not come easy to people. Whedon was also very interested in science fiction and wanted to make something for television that was character-driven and dirty.