One of these is "The Road to Azrael," which didn't see print until 1976. This one is set in Palestine during the Crusades--a time and place Howard was drawn to in his writings on several occasions. As is usual for Howard's Crusader stories, the protagonist is a European warrior. What is unusual, though, is that the story's narrator is a Muslim and that this character doesn't really serve as a sidekick to the hero, but pretty much becomes a co-hero.
Azrael, by the way, is the Islamic name for the archangel of Death. Perhaps one reason the story didn't sell during Howard's life is that the narrator muses just a little too often about riding the road of Azrael, finding or dealing death along the way. (Yes, people keep dying. We get it!) But all that death isn't just a part of the action needed to make this an adventure story. It's also a part of the tale's theme.
The narrator is Kosru Malik, a noted warrior whose name is known among both Muslims and Christians. Early in the story, he meets Sir Eric de Cogan, who is also well-known for his ability to deal death. Normally, the two are on opposite sides of any fighting, but Kosru considers Eric a blood-brother. Years earlier, Eric had saved Kosru's life during the battle for Jerusalem.
Eric is trying to rescue the woman he loves from Mohammed Khan, an important Muslim chief. For Kosru, friendship trumps nationalities or religion, so he helps rescue the girl.
The irony here is that Mohammed Khan is on the verge of forming a new Muslim empire and perhaps kicking the Crusaders out of the Holy Land, so under any other circumstances, Kosru Malik would gladly fight for him.
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As the story come to its conclusion, it seems that the two friends and the woman are doomed--wounded, starving, and exhausted with Mohammed Khan and a few hundred warriors dogging their heels. But the sudden appearance of a surprise real-life guest star might just give them a chance to survive.
That twist at the end might be another reason the story didn't sell, because it comes out of the blue with no significant foreshadowing. But Howard succeeds in making the character involved so awesome that he successfully invokes the Rule of Cool and I'm not bothered by it at all.
So we have a cracking good adventure story interwoven into the idea that the common lusts and envies of leaders can cause them to make decisions that change the course of history.