I don’t remember why I opened this tab, but clearly it’s STILL open because, in the Wikipedia article about Conan author Robert Howard, we find this:

Early 1932 saw Howard taking one of his frequent trips around Texas. He traveled through the southern part of the state with his main occupation being, in his own words, “the wholesale consumption of tortillas, enchiladas and cheap Spanish wine.” In Fredericksburg, while overlooking sullen hills through a misty rain, he conceived of the fantasy land of Cimmeria, a bitter hard northern region home to fearsome barbarians. […]

It was also during this trip that Howard first conceived of the character of Conan. Later, in 1935, Howard claimed in a letter to Clark Ashton Smith that Conan “simply grew up in my mind a few years ago when I was stopping in a little border town on the lower Rio Grande.”