A short story with elements of fantasy and horror. As often in Howard’s stories, there is a link to the Cthulhu Mythos, in this case, mixed also with elements of both Norse Mythology and Catholic Christianity.
It has a rather convoluted history, being in effect an adaptation of Howard’s earlier story Spears of Clontarf, a historical adventure story by Howard focusing on the Battle of Clontarf (1014) and featuring Turlogh Dubh O’Brien or Black Turlogh, a fictional 11th Century Irishman created by Howard. Howard later rewrote “Spears” as “The Grey God Passes”, which was very similar to Spears of Clontarf, but with added fantasy elements. Howard failed to sell the story in either version during his lifetime.