En Sabah Nur was born nearly five thousand years ago in Egypt as a member of a tribe in Akkaba. Even as an infant, he inspired fear. Ugly and malformed, he was abandoned by the tribe to die in the harsh desert sun. However, out of the desert the Sandstormers, a roving band of feared nomadic raiders slaughter the population. Their leader, Baal, found the child crying and he recognized the potential power in the child. He named him En Sabah Nur, literally meaning "The First One", and raised him as his own son.
As En Sabah Nur grew, he surpassed the other tribesmen in intelligence and strength. Everyone in the tribe except for Baal hated and feared him for his inhuman looks and great abilities. Nur did not understand their fear, but hardened his heart against it. Moreover, he believed in the principle that Baal and the tribe lived by, that only the fittest, the toughest, most ruthless and pitiless, tested by hardship, would and should, survive. On the day of his tribal rite of passage into manhood, the seventeen-year-old En Sabah Nur killed three armed warriors of the tribe using only his bare hands.
At this time Egypt was ruled by Pharaoh Rama-Tut. On the day of En Sabah Nur's rite of passage, Baal explained to him that Rama-Tut was no god, as most believed, but a man, who had arrived in a strange vessel. Years ago the tribe had stumbled upon the time-traveler's crashed ship, taken the injured man back to their camp, and nursed the injured and temporarily blinded man back to health. One night he wandered away, taking with him objects the tribesmen had brought from his vessel. Weeks later, his sight restored, Rama-Tut returned, wielding weapons of devastating power and leading the Egyptian army. He massacred the tribe and enslaved the survivors. Although he tortured them, no one revealed the time ship's location.
In actuality, Rama-Tut was a time traveler from the far future who would later become known as Kang the Conqueror. Kang knew that Apocalypse, one of the most powerful mutants who ever lived, and the one who was destined to rule the world, had been born in ancient Egypt. Hence, Rama-Tut had gone back in time to find Apocalypse as a child, raise him, and thereby become the master of the most powerful being on the planet.
On the day of his rite of passage, Baal brought the young Nur to a sacred cave whose entrance became blocked by a cave-in, trapping them underground. After a week of wandering without food or water, they found the remnants of Rama-Tut's time ship within an underground Egyptian tomb. Baal told Nur that he believed him to be a conqueror whose coming was foretold in ancient prophecies, and that Nur was destined to overthrow Rama-Tut. Then Baal died from lack of nourishment, and Nur, whose mutant physiology kept him alive, vowed to take vengeance on Rama-Tut and claim his destiny. Four weeks later he finally made his way back to the surface, but was quickly enslaved.
While a slave, he kept his disfigured lips constantly covered, and Nephri, sister of Rama-Tut's warlord Ozymandias, became attracted to the mysterious slave. Eventually he had a vision of the Egyptian death god Seth, who urged him to become a conqueror. En Sabah Nur was thrown into a pit of snakes, but survived when his superhuman powers activated. He revealed his face to Nephri, who rejected him for his appearance.
At a time when many time-traveling super-heroes, including the Fantastic Four, the West Coast Avengers, and Dr. Strange arrived in Rama-Tut's Egypt, the Pharaoh finally came face to face with En Sabah Nur. Rama-Tut offered to make him his heir if he would swear his loyalty, and then tried to kill him when Nur refused. En Sabah Nur was then shot by the Pharaoh with the same weapon he used to de-power the Fantastic Four. En Sabah Nur was again left to die, but survived with the sudden emergence of his mutant immortality and mass shifting. With his powers flaring, Nur defeated Ozymandias and Rama-Tut himself, who finally escaped back into the future, eventually to take on the identity of Kang. The Fantastic Four went back to their era, thinking the explosion a booby trap. Apocalypse used his abilities to turn Ozymandias into a sand-like being, who would record Apocalypse's accomplishments throughout time. Years later, he revisited Nephri, now an ancient Egyptian Queen, and he mocked her dying beauty, as he was still as he had been years before. He walked away, leaving Egypt.
From then on Apocalypse plotted the conquest of the planet through bringing about wars and conflict, in which the strong would defeat and destroy the weak. Over the centuries he was worshiped by many civilizations under a variety of names. In this Universe, it is important to note, these beings also exist as separate entities.
Apocalypse was most likely confused for them. It is probably at this time that Nur began to have progeny that faithfully followed him as the Clan Akkaba. Offspring of Apocalypse received a portion of his power, those closest related having near identical abilities. Mutants, he was certain, would one day rule the world, with him as their leader, and so he waited. Most of what Apocalypse did during these centuries is as yet unknown.
The Celestial Ship
Centuries later, En Sabah Nur discovered a starship created by the alien Celestials in Mongolia. Apocalypse struck down Saul, immortal guardian of the ship and entered. Unable to understand the technology inside he left again, searching the world for a key to the mysteries inside.
He found this key when the time-traveler known simply as the Traveler killed him. The Traveler's techno-organic blood was mixed with Apocalypse' own blood and Ozymandias returned Apocalypse to the Ship. Inside Apocalypse used his new techno-organic body to link to the Ship and make contact with it. He was transformed and enhanced by Celestial technology, becoming one of the most powerful beings who will ever live.
During the Crusades in the 12th century, Apocalypse arranged for the warrior Bennet du Paris to activate his latent mutant powers for the first time. Renaming him Exodus, Apocalypse made him his servant but later cast him into a deathlike trance when Exodus rebelled against him.
In 1459, Apocalypse led an army to fight Vlad the Impaler, and personally bested him in single combat.
In 1859, Apocalypse awoke from centuries of hibernation in an underground chamber in London of Victorian England. It was here that he first met Dr. Nathaniel Essex, who believed that through selective breeding of humans, he could bring about the rapid evolution of superhuman mutants. Apocalypse offered to transform Essex into a long-lived superhuman being himself to give him the time to further his research, but at a cost: his servitude. Essex accepted, and Apocalypse transformed him into Mister Sinister. However, the Askani, a clan of rebels against Apocalypse two thousand years in the future, transported Scott Summers and Jean Grey to 1859 to prevent Apocalypse from assassinating Britain's Queen and Prime Minister.
Apocalypse, temporarily weakened by a virus with which Sinister had infected him, went back to waiting for the proper moment to reemerge.
Although Apocalypse was awoken in 1897 to deal once more with Dracula, almost a century later, when the world became populated with a new race of superhuman mutants. Apocalypse first reappeared as the employer of the Alliance of Evil, a team of mutants who battled the original X-Factor.
The Four Horsemen
Subsequently, Apocalypse began recruiting his Horsemen. Apocalypse rescued Angel from death and manipulated him into serving him as the Horseman named Death. Worthington's wings had been amputated, but Apocalypse used his advanced genetic engineering techniques to give him new wings with razor-sharp metal-like feathers. Eventually, however, Worthington forsook Apocalypse and returned to X-Factor, and then to the X-Men.
Later, Apocalypse infected the infant son of Cyclops and Madelyne Pryor, Nathan Summers, with a techno-organic virus, having recognized that if this child grew up he would be powerful enough to defeat him and also capable of holding his essence. The Askani once again stepped in and brought the child to their own time period, two thousand years in an alternate future.
To secure a new host body, Apocalypse sought to siphon the awesome energies of The Twelve, mutants of incredible power that were destined to alter the course of history. This time it was Wolverine who fell into the warlord's grasp. The feral X-Man fought his teammates ferociously as the Horseman Death, but broke free from Apocalypse's control. However, Wolverine and his fellow Horsemen had served their purpose. Taking advantage of the distraction afforded by their actions, Apocalypse collected the mutants he required to carry out his plan: Cyclops, Phoenix, Polaris, Bishop, Sunfire, the Living Monolith, Mikhail Rasputin, Cable, Professor X, Storm, Iceman, and Magneto.
The Twelve's energy would be siphoned into the Monolith and then from him into X-man, and as the power went into him Nur would possess the boy a time-tossed teenager possessed of vast telepathic and telekinetic power. As his teammates fell around him, a powerless Cyclops shoved X-Man out of the draining circuit, merging with Apocalypse to create a new evil entity. But the telepathic Phoenix, Summers' wife, Jean Grey, detected her husband's psyche inside the composite being and prevented the X-Men from destroying it. Cyclops was presumed dead by most of his teammates; only Cable and Jean refused to believe he had perished. Investigating rumors and hearsay, they helped him reassert his mind over Apocalypse. With Jean's help, Cable exorcised the warlord and seemingly shattered his essence.
However, after the event known as the M-Day, Apocalypse resurrected, much to the shock of an archaeologist. Looking at the new world, Apocalypse saw a need to act as the savior of the mutant race for once rather than just claim it.
With the aid of Ozymandias, Apocalypse started by bringing to Earth the recently depowered Gazer, then pitting him against the archaeologist in a fight to the death to become the Horsemen War. After Gazer's victory (with the assistance of Ozymandias), Apocalypse approached the newly-legless Sunfire, offering him a slot as the Horseman Famine. Apocalypse then sent his Horseman Pestilence to a military installation to ingest every disease possible.
With three horsemen, Apocalypse went to the Xavier Institute, where he offered salvation which he claimed was truly meant for the first time to the X-Men and 198 mutants seeking shelter. Many mutants, such as Mammomax, Skids, Peeper, Arclight, and Scalphunter, accepted this offer, even though in the case of some it was to counter the affects of Famine. The X-Men, however, went after Famine, who Rogue thought looked familiar. And while War fought against the only manned Sentinel left after Famine's starving effect, Apocalypse waited for the final candidate, Death, who wound up being Gambit.
Apocalypse wished to decimate the human population, and let the survivors fight for the right to be under his rule. He was defeated by the X-Men with assistance from Sentinel Squad O*N*E, the New Avengers and Ozymandias's betrayal. He fled, only to find himself in front of the Celestials, eager to collect upon their deal. As it turns out the Celestials had merely lent him their ship in exchange for a debt of pain from the mutant. He tried to die so he wouldn't have to face them, but was resurrected and taken away.
The Final Horsemen and Uncanny X-Force
Recently, Ozymandias and Clan Akkaba have once again resurrected Apocalypse, but this time in the form of a child. In this form, Apocalypse seemed to have no memory of his past or his previous disregard for life. Ozymandias and the Celestial Ship took to tutoring and indoctrinating the child Apocalypse. To protect this young En Sabah Nur, The Final Horsemen, mutants collected over centuries, were activated. War, Pestilence, Famine, Death battled X-Force on the Blue Area of the Moon and nearly defeated them. However, due largely to Fantomex's illusions, the team apparently killed the Horsemen and Ozymandias. When they discovered the young Apocalypse, the team fought over what to do with him. The issue was rendered moot when Fantomex shot the boy in the head.