Sanjar Javeed is the illegitimate son of King Shapur II of Persia, born around 325 A.D. Though his father was revered as beloved, generous, and compassionate, Sanjar never received these emotions from his father as he was born to a servant mother. Attempting to gain the love of the people of Persia, Sanjar would steal treasures from his father and give them to the townsfolk. Unaware of his mutant ability to transmit terminal diseases, his gifts to the townsfolk only spread death, even killing his father.
Sanjar was watched by the eternal mutant Apocalypse and selected as his Final Horseman Death in the event that all other plans of Apocalypse failed. He fought Wolverine, and even Wolverine's claws couldn't kill him. Death was later tricked by Fantomex into leaving X-Force alone.
After Apocalypse was killed by the X-Force, and Archangel became his successor, all Horseman went over to his side. When Sanjar tried to infect Deathlok with diseases, Deathlok killed him by beheading him, since no diseases could affect him.
Sanjar somehow survived the fight with Deathlok and ended up creating and running a school alongside adventurer Jimmy Woo.