This myth made me smile. And not only because it's about one of my favorite treats (if you're ever overcome with the desire to get me something, I'm particularly partial to rose, lemon, and bergamot flavors).
The myth is quite simple: That C.W. Lewis invented a candy called "Turkish Delight" that later enterprising candy makers made into a real treat. Much like how one can find recipes for Butterbeer from the Harry Potter series today.
Fortunately, the world did not have to wait until 1950 to enjoy the deliciousness that is Turkish Delight. Turkish Delight as we know it today was invented in 1777 by Bekir Effendi who owned a confectionery shop in Istanbul.[*] The family still owns the shop and it still makes Turkish Delight. The confectionery is called Ali Muhiddin Haci Bekir Confectioners today (the link takes you to their website. I suggest you check it out!)
I suspect C.W. Lewis simply gets the credit (or the blame) because today it's not a common candy, so most people's first brush with it comes from reading about it in his novels or from watching the movies based on his novels.
If you'd like to try to make it yourself, you can find a recipe to make Turkish Delight here.