In 1980, I wrote the roleplaying game "Call of Cthulhu". When it was published, everyone I knew who had heard about Lovecraft had heard about him because I had told them personally. Lovecraft was vanishingly obscure.
I knew Lovecraft was an unknown. I expected Call of Cthulhu to sell a couple thousand copies to the few hard-core Lovecraft fans in the world, and then vanish. But I put my heart into it because of my own love for Lovecraft.
Instead, the game actually promulgated Lovecraft, and spread knowledge of him. Many many folks played Call of Cthulhu, and many more didn't play it, but knew about it. I have had literally thousands of people walk up to me at conventions and tell me that they read Lovecraft after playing Call of Cthulhu.
It is my proudest achievement to have been a tiny part of helping bring cosmic horror to so many.