|Cover artist||Kazuhiko Sano|
|Genre(s)||Science fiction, Alternate History|
|Followed by||Curious Notions|
Gunpowder Empire, Tor, 2003, is the first novel in the Crosstime Traffic Series. It follows the adventures of the Solters family, who spend every summer in the alternate universe called Agrippan Rome, more precisely in the city of Polisso, in the Dacia region, which is Romania in their reality. Agrippan Rome is a world where the Roman Empire never fell, thanks to Marcus Vipsanius Agrippa's survival against disease, which let him lead the Roman armies against barbarians, bring Germania into the Empire (unlike in the home timeline) and annexing Dacia a century early.
The Solters setup shop in Polisso, selling pocket watches ("hour-reckoners"), sharp razors, mirrors, and Swiss knives, all trinkets slightly above the technological know-how of the people. Things start going awry when Mrs. Solters falls ill. She and Mr. Solters leave for the home timeline, leaving their children Jeremy and Amanda behind. All would be well, except that soon after Jeremy and Amanda lose the communication link to their home timeline, and the neighboring kingdom of Lietuva (Lithuania and several neighboring nations in the Solters' home reality) has once again declared war against Rome, and the siege of Polisso begins.
In "Alternate History: The How-to of What Might Have Been," Turtledove says that he wanted to write a story using a reversal of the Battle of the Teutoburg Forest as a break-point much earlier, but "It took me more than twenty years to come up with a story to follow on changing things there."
The book's plot has much in common with Household Gods, written by Turtledove in collaboration with Judith Tarr - though that book concerns time travel back to the OTL Roman Empire. Both books depict the daily life of a provincial Roman city from the point of view of modern American(s) marooned there, and both deal prominently with such issues as facing a society where slavery is taken for granted, and surviving a foreign invasion of the Imperial territory.
This is the only Crosstime Traffic novel where both POV characters are from the home timeline.
References to other Turtledove works
Further alternates are discussed when Jeremy is in school, but never revisited in the series. One, where North America was colonized by Vikings, may be the world of "The Wheels of If"/"The Pugnacious Peacemaker". Another, where North America remains a contented part of the British Empire in the 2090s, may be the world of The Two Georges. It is said that in some alternates Nazi Germany won World War II, which may be the worlds of In the Presence of Mine Enemies, "The Last Article," "The Phantom Tolbukhin," and/or (retroactively) "Shtetl Days".
By contrast, in one alternate Spain successfully invaded England with the Armada, but there is reason to believe that this is not the world of Ruled Britannia, which uses a similar POD. Likewise, there is reference to an alternate where the Confederate States won the American Civil War, but there is reason to believe that this is neither The Guns of the South nor Southern Victory.
- We Install and Other Stories, p. 20.