Alternate history is a genre of fiction that, although connected to science fiction, has its own rich history and lineage. With its roots in the writings of ancient Rome, alternate history matured into something close to its current form in the essays and novels of the nineteenth century. In more recent years a number of highly acclaimed novels have been published as alternate histories, by authors ranging from bestselling science fiction writers to Pulitzer prize-winning literary icons. The popularity of the genre is reflected in its success on television, where original concepts have been...