Wicked cool!
About that Lovecraft paperback for American GIs, I found this by Roberth Bloch in an introduction to some Lovecraft collection. His introduction is called "Heritage of Horror" and I think the book is called something imaginative and risky like "H P. Lovecraft":
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Lovecraft's work survived it all. It even survived Derleth's imitations of his style and subject matter, which he began writing in the forties. Derleth had won deserved praise for his "Solar Pons" pastiches, based on the Sherlock Holmes tales of Conan Doyle. But his pseudo-Lovecraft efforts were less convincing. Using a line or two from Lovecraft's commonplace book scarcely justified calling the total work a "posthumous collaboration." And when he abandoned this pretext his attempts to convey the essence of Lovecraft's style didn't come off; he sounded the notes but lost the music.
It was Derleth who constantly used the term "Cthulhu Mythos" to describe Lovecraft's cosmic concepts. Unfortunately, his own writing involved a distortion of its meaning that may have derived from his own status as a lapsed or lax Catholic. In any case, he divided Lovecraft's Great Old Ones into what in effect were the Good Guys and the Bad Guys, fighting over possession of the earth instead of the ranch. Some later imitators picked up on this, straying far from Lovecraftian logic.
But when considering Derleth's influence, one single fact remains all-important--he championed the revival of interest in Lovecraft's work. After Donald Wandrei's service in World War II his Arkham House activity was largely limited to editing Lovecraft's letters, eventually published in five volumes. Derleth, however, continued to keep the stories in print, reissuing portions of the original collections under other titles. When fantasy anthologies began to flourish, he sold one-time reprint rights to various stories, including those in public domain, and until his death in 1961 he claimed control of the literary estate.
As early as 1945 he compiled a paperback Lovecraft collection for an Armed Services edition. Its unexpected popularity with a wide readership encouraged later reprinting efforts by other paperback publishers here and abroad. Gradually this continued exposure led to the formation of a new fandom, enthusiasts interested in every aspect of the man and his work. Following recognition on the part of foreign critics, Lovecraft--like his predecessor, Edgar Allan Poe--finally came to the attention of the American literary establishment.
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