[1] The stories are set in a world in which Homo erectus, along with various megafauna, survived to the modern times in the Americas as the Native Americans along with any other human cultures.

Turtledove was inspired to write the story by a Stephen Jay Gould article that speculated as to how humanity’s distant cousin, Australopithecus, would be treated if that species had survived.

[3] 1610: At the colony of Jamestown, Virginia, Edward Maria Wingfield must rescue his infant daughter from the tribe of wild sims who kidnapped her.

[3] 1691: Thomas Kenton, a scout from Virginia and descendant of Edward Wingfield, and his faithful sim companion Charles, explore the interior of North America.

A race is held in a commonwealth bordering the New Nile starting in Springfield and ending in Cairo, with one of the hairy elephant-pulled trains they threaten to replace.

2) In this story it is learned that England's American colonies broke off into a new nation - the Federated Commonwealths of America - in 1738, and westward expansion began much sooner than in our history, due to the lack of indigenous humans in the regions to be colonized.

In Turtledove works, it is common for historical figures to have fictitious offspring (as with Edward Wingfield's daughter and her own great-grandson Thomas Kenton above) as a result of the butterfly effect.

1812: Henry Quick, a trapper in the Rocky Mountains, is wounded by a bear and is nursed back to health by sims in exchange for making tools such as cups and bows and arrows.

[3] Science fiction author Orson Scott Card also gave a good review for the novel complimenting Turtledove especially on Freedom for the use of a sim's point of view without "sentimentalizing and anthropomorphizing until the true differences between species are erased.

[6] Vilest Beast, And So to Bed, Around the Salt Lick, The Iron Elephant, and Though the Heavens Fall were all originally published in Analog Science Fiction and Fact.