Pedantry - Heroic

Before a massive retcon during The Burning Crusade, the Draenei were an alien race of sorcerors and warlocks who corrupted Sargeras, leading to the latter forming the Burning Legion, while the Eredar were a subservient demonic race. After the retcon, the Eredar and Draenei were made one species who were split by the corruption of the Eredar by Sargeras.