Winters’ counterfactual (of a world in which the 1860 U.S. presidential election resulted in a political compromise, maintaining the institution of slavery) runs much farther into the future than most such novels–to the present day. It is shocking to see a modern world, with familiar brands and technology such as cell phones, in which slavery still exists in the southern U.S.

One of the book’s strongest points is that it has a more realistic view of technology, including data visualization, than most contemporary fiction. Unfortunately this is not enough to redeem it, as several key plot points are implausible even in the elaborate and interesting world of this novel.