Every Alternative

A work of alternative history fiction can be set entirely within an alternative timeline, like Poul Anderson's "The House of Sorrows," or can involve travel between such timelines, like HG Wells' Men Like Gods or Anderson's "Eutopia" and his Old Phoenix sequence.

As far as I can see, every alternative history narrative by SM Stirling soon or later acknowledges multiple timelines? Although the Emberversers do not know it (yet), the Nantucketers have gone elsewhere/when.

The premise inherently entails the possibility that the alternative histories of Wells, Anderson, Stirling etc coexist in the multiverse and could be referenced in later works by other authors. The DC Comics multiverse even included one Earth where no one had gained any superpowers. The only place to read about superheroes was in comic books although a supervillain from Earth 3 commented that this sounded unlikely.

Why is the Emberverse called that? Volume II should arrive today. We remain very close to Poul Anderson while enjoying a whole new slant on one of the basic sf premises. There have been at least three TV series based on the Germans winning World War II, two of them adapted from novels by Philip K Dick and Len Deighton, and one of the DC universes had superheroes fighting a Nazi world dictatorship. Anderson has a World War II fought against a Caliphate and Stirling has the Draka winning the Final War. Most timelines have problems.