L. Sprague de Camp’s Lest Darkness Fall first saw light as a short story in the December 1939 issue of Unknown magazine before being expanded into a full novel for hardcover publication by Henry Holt & Company in 1941. Unknown was the companion magazine to Astounding, both of which were edited by John W. Campbell, the godfather of the “Golden Age of Science Fiction”. Campbell had taken the reins of Astounding in 1937 and had almost immediately turned it away from its freewheeling high adventure origins towards more scientifically plausible and therefore “realistic” stories. In 1939, Campbell launched Unknown with a very similar mandate towards fantasy fiction; his direction to writers was “For Astounding I want stories which are good and logical and possible. For Unknown, I want stories which are good and logical.”
As an aeronautical engineer by training and a paleontologist, historian and educator by inclination, L. Sprague de Camp was an exemplar of the new breed of scientifically savvy writer that Campbell was cultivating. De Camp’s essentially rationalist worldview seems to have given him trouble in depicting the truly impossible, at least in his nominally science fiction works. It makes sense then that he’d quickly gloss over the mechanics and metaphysics of time travel in Lest Darkness Fall in favor of playing to his strengths, in this case a deep knowledge of Late Antiquity, specifically the Gothic War (535-554) that devastated the Italian peninsula and sent it into a state of decline that was only reversed with the coming of the Italian Renaissance.
Lest Darkness Fall was de Camp’s first solo novel, but even then some of his tropes were in evidence, such as the highly educated and rational protagonist making his way in a strange new world, both aided and opposed by often comical or even buffoonish locals. De Camp’s writing can be compromised at times by the feeling that he’s holding himself above the material or at least failing to fully embrace it, but thankfully that’s not the case with Lest Darkness Fall. Padway’s dry wit rarely devolves into snark, and his 20th century education and native intelligence aren’t always enough to carry the day–ultimately Padway relies on persuasion as much as intellect.
Lest Darkness Fall’s balance of well-developed characters and careful extrapolation of history made it a cornerstone of the Alternate history sub-genre of fantastic fiction to this day as witnessed by its frequent reprintings over the last 80 years. It has also drawn reponses in the form of the short stories “The Man Who Came Early” (1956) by Poul Anderson, “The Deadly Mission of Phineas Snodgrass” (1962) by Frederik Pohl, “To Bring the Light” (1996) by David Drake, and “The Apotheosis of Martin Padway” (2005) by S.M. Stirling. The current king of alternate history fiction Harry Turtledove recently tweeted that the book changed his life: “ L. Sprague de Camp’s LEST DARKNESS FALL. Without It, I wouldn’t have studied Byzantium, and my whole life would be, well, an alternate history.”
The Ballantine Books 2nd paperback printing (1975) feature a Darrell K. Sweet cover illustration, but the groovy typography steals the show:
Gary Gygax prided himself on being an amateur medievalist, so it’s not surprising that he cited Lest Darkness Fall in Appendix N despite the only overtly fantastic element being the lightning bolt that sends Martin Padway back in time. Padway’s efforts to keep the light of civilization burning are not dissimilar from the “domain game” aspect of Dungeons & Dragons. Aside from that, Padway’s depiction as the lone rational man in an uncouth world echoes is the essence of nerd self-image, and de Camp and Gygax are essentially proto-nerds made good….
Reading Resources:
Lest Darkness Fall & Related Stories (trade paperback/Kindle ebook)
Additional Reading:
A Connecticut Yankee in King Arthur’s Court (public domain ebook) – Mark Twain’s 1889 novel is the most obvious antecedent to Lest Darkness Fall, although it is overtly satirical rather than an exercise in alternate history.
If you are in Brooklyn and want to join the IRL book club, then come over here.
The list of books we will discuss are outlined within this link.
And finally, the in-print omnibus, anthology, and online resources are living over here.
Appendix N Book Club 
I really enjoyed this one (maybe more than Hoi and Jeff?). I think the trope the modern engineer goes back in time and thrives and changes history is funny. Of course, Harold Shea does the same thing with his fencing skills.
An alternate interpretation of this that I really liked was Tim Powers’s The Drawing of the Dark. A modern character goes back in time and – guess what – his ability to understand the medieval (renaissance?) world is about as effective as a historical character’s ability to understand our own.
As always, great podcast!
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