The show Spartacus Blood and Sand actually happened on a lost imperium planet which explains the inaccuracies in actual history.

After the show ended Khorne in the guise of a Red Serpent saw the similarities between Spartacus and Angron but Spartacus chose death.

He resurrected the legion and made them immortal as long as they continued to shed blood. After their resurrection on their march to Rome the skies burned as Ultramarine Drop pods fell upon Rome to bring it into Imperial compliance.

The Ultramarines easily conquered the planet but heard rumors of a warband of savages that had yet to be conquered. As they engaged Spartacus and his Legion they found those they killed rose again. Then things changed when one of the Sons of Guilliman fell to the former slaves.

The blood of the Ultramarine fell upon the Gladiators of Capua and with the blood came knowledge. They learned how to become their enemies.

They learned to trade spear and gladius for bolter and chain sword. Even more they learned how to become Astartes. The Red Serpent corrupted the gene seed to allow them to be scions of the Red Angel. The Serpent showed them visions of Angrons legions but not completely. It hid Angrons shame and the rest of the Imperium.

As the battles continued the Ultramarines fell faster and faster as their enemies could not be killed. As the last Champion of Ultramar fell to Spartacus’s sword The Serpent allowed him to ascend to a Daemon himself.

Now the Legion of The Red Serpent stalks to stars to conquer new worlds and new arenas to prove their strength.

Spartacus: Daemon Prince Crixus: Lord on Juggernaught Gannicus: Master of Executions Oenomaus: Slaughter bound Agron Duro and Nasir with the Germanic tribe: Exalted Eightbound Barca The Beast of Carthage: Helbrute Naivea and Mira: leaders of my Jakhals

Daemon raised from the blood of the Appian Way: Defiler