All of our 1941 Retro Hugo Award coverage is indexed here.
I have to confess that I’ve got a fair amount of reading to do in order to get everything “novel” under my belt from 1940. I’ve read a few of the more recognizable stories – the Heinlein, the van Vogt, some of the Hamilton, Smith’s epic, the Wellman. My Hubbard reads have been conflicted by my desire to not fund a certain non-church, but if there is any year that could possible justify breaking that embargo, 1940 is it: Final Blackout is generally considered both a golden age classic and perhaps the best story Hubbard turned out. Typewriter In the Sky is an early example of alternate realities and the “author as god” concept.
Absent the reading I still need to do, I think the stand-outs in this list are Slan, Gray Lensman and If This Goes On… (though I’ve only read that in the fix-up Revolt in 2100).
I can see a fair number of folks looking to the Oz story; Brer Rabbit for the fact that the rabbit’s tactics have been employed in SF tales almost from the beginning; Captain Future – although beloved by many, these novels remain firmly in the pulp era and I doubt that any discerning audience today will do anything but give them short shrift; the same could be said for Lensman, but there’s more nostalgia associated with Smith than there seems to be for Hamilton…and far more associated with Jack Williamson, but his inclusion will depend, I think, on the quality of the Weird Tales story included here.
This is not presented as a complete and comprehensive list of all of the novel length SF/F/H published in 1940. The ISFDB.org magazine indexes were used, as were google searches for “novels published in 1940 and the WorldCat database. Suggestions and additions will be gratefully received.
Black World Raymond A. Palmer
Brer Rabbit Again Agnes Murray Iverach; Joel Chandler Harris; G M Richardson
Calling Captain Future by Edmond Hamilton
Captain Future’s Challenge by Edmond Hamilton
Captain Future and the Space Emperor by Edmond Hamilton
Final Blackout by L. Ron Hubbard
Gray Lensman by Edward E. Smith
If This Goes On …by Robert A. Heinlein
The Indigestible Triton by L. Ron Hubbard
A Million Years in the Future by Thomas P. Kelley
On the Knees of the Gods by J. Allan Dunn
The Reign of Wizardry by Jack Williamson
Slan by A. E. van Vogt
The Spark of Allah by Marian O’Hearn
Sons of the Deluge by Nelson S. Bond
The Time-Wise Guy by Ralph Milne Farley
The Tommyknocker by Thomas Calvert McClary
The Triumph of Captain Future by Edmond Hamilton
Typewriter in the Sky by L. Ron Hubbard
West Point 3000 A.D. by Manly Wade Wellman
The Wonder City of Oz by L. Frank Baum
As an added bonus(?), an episode of Captain Future anime