Suspense in the 1920s

One of the fascinating things about Call of Cthulhu , originally released in 1981, is the way that Chaosium's early advertisements tended to, if not actually downplay its connection to the works of H.P. Lovecraft, place it on an equal footing with other elements, such its 1920s setting or a broader "investigation of the occult." 
Anecdotally, this approach seems to have worked. Though HPL was well known in some corners of the hobby at the time, he certainly didn't enjoy the same wide level of fame he now possesses. Given that, promoting it as a more general horror game makes sense. I know plenty of people my age whose first introduction to Lovecraft was through Call of Cthulhu, much in the way that they learned about Robert E. Howard's Conan from the pages of Marvel comics. Likewise, CoC was one of the earliest RPGs set in the 1920s, predating TSR's Gangbusters by a year (though FGU's Gangster! appeared in 1979). I know that certainly appealed to me (and still does – it's my preferred era in which to play the game). 
The older I get, the more I find myself in awe of what Chaosium accomplished in the first decade of the hobby. Better late than never!