Over at Rough Edges, friend of TC James Reasoner has recently posted a blog about this book by the nearly-forgotten writer Perley Poore Sheehan:

I don’t know if Robert E. Howard ever read this story, but it’s certainly possible. In the opening chapters, Abu is very reminiscent of Conan and other Howard heroes as he wreaks havoc on his enemies and leads a rebellion against the rich, powerful, and evil masters of the unnamed African nation where the story takes place. There’s slaughter right and left for a while, but then Abu emerges victorious and has to deal with ruling an unexpected kingdom while also trying to expand it. There’s also the matter of Khadija, the beautiful blond prisoner who was supposed to be the bride of the overthrown Arab merchant. She and Abu fall in love at first sight, but Abu has sworn a vow of poverty, sobriety, and chastity until he has spread his empire over the entire world and freed all the slaves everywhere.

Here’s the blurb:

Abu, The Dawn-Maker is a fast paced, bloody tale of a slave revolt in Portugese East Africa.

Following the death of his master Abu is declared, a wonder, a miracle, a messiah who would be a new dawn to all the down-trod peoples of the world. Drawn by his Luck and charisma, thousands join his army. The cities fall to his armies but close to Abu lies the seeds of destruction — a woman. Khadija! She has seen in him a vitality that sets her afire. She would have him for her mate. But Abu has made a solemn vow – of sobriety, of poverty and above all, of chastity — until his great work is done.

Here’s an excerpt of Abu, courtesy of Bill Thom from Coming Attractions:

Before he could repeat the cry Abu seized him by the arm and throat, bent him over backward. Al-Marwazi in that crushing grip apparently lost courage.
“Your bauble—I’ll get it back for you,” he gasped.
Abu laughed.
He twisted and crushed, twisted and crushed. There was scarcely a sound, except that of soft silk garments deranged, the shifting of feet on the ground. There was a moment when Abu was kneeling on the thing he had pressed down under him.
“Allah!” he cried. “He is dead. I have killed Al-Marwazi!”
The rich man had managed to get out his dagger, but it had been too late. It was slipping now from the smooth, fat fingers of his right hand.
And Al-Marwazi, as though he had forgotten all about the struggle that had barely begun, let it slip, lay with his face to the earth.
Abu picked up the dagger and pressed it home.
“Allah!” he repeated. “He is dead. And I–”
It was evident that the new thought had had difficulty in making its presence known; but once it was realized, Abu reeled to his feet like a drunken man.
“And I,” he gasped, “I am free!”

It looks interesting. Beb Books publishes this volume. Their catalogue also includes The Moon Pool and Conquest of the Moon Pool; these two stories by Abraham Merritt appear here in uncut and unabridged versions for the first time since their original publication in the Pulp magazine All-Story Weekly in 1918 and 1919 (Merritt edited and combined these tales to make a single novel out of both as soon as 1919).