Arabian Desert, circa 640 AD
Majid ibn Abdul-Yasu stared at the night sky with his son, Yusuf ibn Majid, standing beside him. “Abbi”, his son asked, “why are the stars there?” Majid initially responded “because our Lord put them there”, only for Yusuf to ask “but why did He put them there”, to which Majid had no answer. This conversation between father and son was interrupted by cries of panic and calls to battle. Another Bedouin tribe had raided their encampment. A great battle ensued, and Majid’s tribe(the Banu ‘Alaa) had emerged victorious. Majid would return to his tribe’s encampment.
He called out for his son, but it would be to no avail. He would soon realize, but take much longer to accept, that his son had died in the fighting. This event would live with him for years to come, and he would take “Abu Yusuf”, or “father of Yusuf”, as the title by which the world would know him. He would nevertheless continue on, eventually becoming the sheikh of the Banu ‘Alaa tribe. His story had only just begun.
From “History of Arabia” by Abdul-Yasu ibn Ismail
After becoming the sheikh of the Banu ‘Alaa, Abu Yusuf set out to unify the Arabian peninsula under his rule. This would take five long years to accomplish, but it happened nevertheless. Abu Yusuf’s unification of Arabia took place within the context of the larger war between the Palmyrenes and Sassanids. The Sassanid Shah, Ardashir III, had taken Palmyra and forced Palmyrene Emperor Antiochus II to flee northwards, establishing his capital at Byzantion[1]. Despite the Persians’ initial successes, the Palmyrenes would ultimately retake Palmyra and sack Ctesiphon, winning the war.
Having defeated the Persians’ Arabian proxies, Abu Yusuf prepared for a full invasion of the Sassanid Empire. Ardashir III had died in the conflict, and his young son Yohnan II was placed on the throne, with his brother Shapur made regent. Abu Yusuf’s armies would successfully sack Ctesiphon, holding the Shah and regent captive, and continued to march further into Persia. Persia was in a succession crisis, as Ardashir’s brother Kurush claimed that Yohnan was illegitimate and thus he should be Shah. Abu Yusuf’s forces would finally defeat Kurush’s at the Battle of Hamadan, ending the Sassanid Empire. With Persia fully incorporated into Abu Yusuf’s burgeoning empire, he turned his eyes west; to the holy land, occupied by the pagans whose ancestors had murdered Christ.
[1]I might or might not have OTL Constantinople become a major city ITTL. It’s at an ideal location, and is much more easily defensible than Palmyra, but without Constantine it’s still a small-ish city away from the centers of power