Night Elves with an addiction to arcane magic became the offshoot known as the High Elves. Known in their native tongue as Quel’dorei (“children of the sun” / “highborne”), they were originally followers of Queen Azshara and helped her in her research of magic and demons. Azshara, feeling they were inherently superior to her subjects who did not practice magic, named her followers “Quel’dorei,” meaning “Highborne.” Azshara and the Highborne were responsible for the invasion of the Burning Legion and for the destruction of the Well of Eternity, a highly magical and sacred lake which once stood in the centre of Ancient Kalimdor. The Highborne, obsessed with magic and seeing that their dreams of magical power could never be realized under the rule of their magic-hating brethren, went into self-imposed exile to create a new, magical civilization for themselves. They found such a place across the sea, on the continent of Lordaeron. Travelling the continent for centuries, the Highborne slowly began to look less and less like the other Night Elves on Kalimdor, owing to their separation from the World Tree. They finally settled in the North, and were responsible for the destruction of the great Troll empire. Upon the introduction of Humans from the south, the High Elves (as they were now called) joined forces with the Humans, and welcomed them to their kingdom of Quel’Thalas.
After Arthas, the traitorous human prince, had been corrupted through picking up the cursed runeblade Frostmourne, he set out on a campaign to erase all the forces who might oppose the Burning Legion before it was summoned. When erasing the nation of the High Elves he managed to kill two birds with one stone; he defeated one of the nations mighty enough to repel the Burning Legion and he got to use the High Elves Sunwell, from which they got their magical abilities, to raise the Lich Kel’Thuzad.
A sizable number (estimated to be 20%) of High Elves survived the destruction of their homeland and a very small number joined Jaina Proudmoore’s expedition to Kalimdor and currently live on Theramore Isle. They are able to satisfy their addiction to magic there with the Night Elf Moon Wells. Most however became the so-called “Blood Elves”, who turned to darker sources in their quest to satiate their thirst for magic and restore their people to the glory they once enjoyed.
These Blood Elves (“Sin’dorei” in their own tongue) adopted the name in memory of their fallen brethren, and turned to corrupted magic that drew upon demonic forces to avenge their lost kingdom. Most of them were left in charge of the defense of Lordaeron and Quel’Thalas to drive out the Undead, led by Prince Kael’thas. The racist Human general in charge of the force, Lord Garithos, despised the Elves. He finally recalled all Human and Dwarven units to the front line, leaving only the meager Elf forces to defend against the rampaging Scourge. With no other options, the Blood Elves were forced to ally with the Naga, an action Garithos had specifically forbidden. He subsequently had them imprisoned in the ruins of Dalaran, where they were eventually freed by the Naga. Upon escape, they agreed to travel with the Naga to Outland, where they hoped to find the Naga’s master, Illidan Stormrage, to ask his help in finding a cure for their racial addiction to magic. Other High Elves, those that survived Quel’Thalas’s destruction and didn’t fall to the primal rage that fuelled the Blood Elves’ descent into dark magic, now consider the Blood Elves to be not only traitors to the Grand Alliance, but also a stain upon the memory of their fallen brethren.
They are the new Horde race in The Burning Crusade expansion pack, and they reside mainly in Quel’Thalas, where they are regenerating to their old strength. The only true friends the Blood Elves are presented with are the Undead Forsaken, who share in their ultimate fate against the Undead Scourge.
Within the current World of Warcraft timeline, the Blood Elves have largely been successful in retaking Silvermoon City and its surrounding areas from the Scourge forces, however the land still bears the scar of the battles fought. In addition to outlying towns within the contested Ghostlands, the Blood Elves maintain a number of outposts, towns and bases of operation within the realm of Outland.
While the overwhelming majority of the survivors followed in their leader’s stead and ultimately severed their ties with the Alliance, a small segment of the High Elf population elected to remain loyal to the Alliance as a result of varying motivations. High Elves can currently be seen living alongside humans and dwarves within the port city of Theramore, maintaining a variety of hunting lodges throughout northern Lordaeron and also amongst the recently reunited Outland Expeditionary forces. This smaller faction also feels the effect of the Sunwell’s loss upon their people, but abhor the selfish, arcane-driven practices of their Sin’dorei cousins.
It should also be noted that while a rarity, true light-embracing Quel’dorei Paladins do exist within the ranks of the Alliance as opposed to the Sin’dorei Blood Knights who have obtained their powers through the enslavement of a creature of light, the Naaru. As High Elves are not available as a playable race within World of Warcraft, such characters exist solely as NPC’s.