The blood elves, prior to the events of Warcraft III, were simply called the quel'dorei, or "high elves." Before that, they were night elves that had been exiled from Kalimdor for using arcane magic, an act that had been forbidden by the druids of the kaldorei and punishable by death. These elves, undergoing severe bouts of withdrawal due to not being able to practice what came naturally to them, were not put to death but instead exiled to the Eastern Kingdoms under the leadership of Dath'Remar Sunstrider. Upon arriving in the Eastern Kingdoms, the quel'dorei discovered several key things:
- There was some sort of evil lurking underneath Tirisfal Glades that slowly drove them mad until they decided to resettle.
- Humans existed -- primitive ones. As they didn't pose much of a threat, they were summarily ignored.
- Trolls existed -- primitive ones. Savage, bloodthirsty trolls from the great Amani Empire.
- Building homes on former sacred troll ruins? Terrible idea.
Despite number four, the high elves beat back the Amani trolls and then went ahead and built Quel'thalas on former sacred troll ruins, not because they really wanted to anger the trolls but because the spot had an unusually large amount of ley
energy, perfect for practicing arcane magic with. The high elves then created the Sunwell
at the convergence of all of this ley energy, with a vial of water stolen from the Well of Eternity
. The Sunwell was everything
to these elves -- it was a source of power to their magics and gave them what they'd been lacking ever since leaving Kalimdor and severing their ties to the original Well and the World Tree, minus the immortality.
The trolls spent about 3,000 years planning and perfecting their next assault on the high elves, an assault that sparked the Troll Wars. Now led by Dath'Remar's descendant Anasterian
, the high elves soon found themselves fighting a war that they appeared to be losing. In desperation, Anasterian turned to those formerly primitive humans, now known as the humans of Arathor and led by King Thoradin
, for aid. Thoradin agreed to help after Anasterian offered to teach 100 humans the ways of magic -- and after all, Thoradin mused, if the trolls were such a threat to the high elves, they'd soon come after the humans as well. The Amani were defeated again, and in gratitude for their aid, Anasterian pledged the eternal support of the elves to the Arathi -- the bloodline of King Thoradin.
For almost 3,000 years, the high elves continued to quietly practice their magic in peace, until Anduin Lothar
came calling and asking for the high elves' aid in the fight against the orcish Horde of the Second War
. Anasterian was reluctant to send troops to support this new Alliance, partially because it seemed a war between the younger races that the elves should just stay out of, and partially because it appeared this Horde bore no particular threat to the lands of Quel'Thalas. Regardless, he sent a small contingent of soldiers to assist the Alliance, as he couldn't in good faith break the oath he'd given to Thoradin centuries before.
When the Horde began burning the borders of the forests of Quel'Thalas, Anasterian abruptly realized how much of a threat the forces actually were
and threw his full support behind the Alliance. During the course of the Second War, Anduin Lothar fell in battle to Orgrim Doomhammer, ending the Arathi bloodline for good. The Horde was successfully pushed back, largely due to its own internal conflicts, and the Alliance won. But once the war subsided, the high elves largely chose to withdraw from the Alliance, though some stayed behind to continue helping the humans and other races.
Why? Well, largely because they were a reclusive people who wanted nothing more to be left in peace and continue their work with arcane magic. The night elves had essentially shoved the high elves out of Kalimdor without bothering to hear the quel'dorei's side of things. The magic that was their way of life had been forbidden, and thus they were already a bit bitter regarding the world at large. Once they'd established the Sunwell, the trolls interfered with their plans, and an alliance was necessary -- and King Thoradin was a good leader who impressed Anasterian, hence the oath. Lothar was the very last of Thoradin's bloodline, and thus Anasterian was bound to help him, despite the fact that he didn't really know Lothar at all. Once Lothar died, there was nothing left to hold the high elves to the Alliance.
On top of this, it could
be argued that the humans were the ones responsible for the Horde's coming to Azeroth, as it was the human Medivh's
meddling that brought the Dark Portal into existence in the first place. The fact that is skimmed over here is that if Anasterian had not agreed to teach those hundred humans magic in the first place, there would be no human mages, no Kirin Tor, no Guardians, and thus no Medivh
. So really, when you take a critical look at it, the high elves had just as much of a hand in bringing about the creation of the Dark Portal as the humans did.
Regardless, the high elves were kind of like a snooty version of Switzerland -- they didn't want to get involved in anything. They simply wanted to remain a neutral party. The high elves just wanted to disappear, as far as the rest of the world was concerned, but they were never allowed the opportunity. When the Third War
came to pass, Arthas Menethil
took up Frostmourne and fell under the sway of the Lich King
. His first task was to raise the dead necromancer, Kel'Thuzad
, and in order to do this, he needed a source of power to use for the spell -- the Sunwell. Arthas advanced on Silvermoon with his Scourge army, laying waste to everything in his path. One particular thorn in his side was the high elf Ranger General Sylvanas Windrunner
, who held him off as long as she could before she was slain by Arthas.
Thousands of lives were lost, and the high elves found themselves completely outnumbered. Anasterian Sunstrider made his final stand before he, too, fell before Arthas and his army's might. The Sunwell was corrupted beyond redemption by the spell used to raise Kel'Thuzad from the dead, and the high elves abruptly lost not only their source of magic, but also about 90% of their population. In the face of this, Anasterian's son Kael'thas Sunstrider
returned to Quel'Thalas from Dalaran, gathering the remaining survivors of his people and dubbing them blood elves, or sin'dorei, in memory of the countless elves that had lost their lives during the attacks. Kael'thas, formerly one of the six high council members of the Kirin Tor
, was now left with the task of leading the few survivors and trying to fill in his father's footsteps.
Kael'thas did not share his father's wishes to remain out of sight. As a long-standing and respected member and one of the Council of Six that ruled the Kirin Tor; he worked with humans and other races without a second thought. Perhaps unwilling to follow in his father's viewpoint, given that Anestarian's "leave us alone" policy had led to the near extinction of his people, he took the strongest of those that were left and sought to help the Alliance with their fight against the Scourge. These are all speculations, of course, but what is obvious is this: Kael'thas and the blood elves needed help. The Alliance could offer that help -- but the larger outlying problem was the Scourge, and there was no way the blood elves could extinguish the Scourge on their own.
He left behind Ranger General Sylvanas' second-in-command, Lor'themar Theron
, as Regent in his stead, along with the remaining survivors that were too weak to help fight, and told them to begin work on rebuilding Silvermoon. What he didn't expect was the attitude of the Alliance when he showed up offering his people's services in the ongoing war. The de facto leader of Alliance forces in Lordaeron, Grand Marshal Garithos, treated Kael'thas and his people like utter trash, largely due to his racist attitudes toward the elves. It was Garithos' belief that the Alliance never should've accepted the elves into the Alliance in the first place, and he took out these beliefs by ordering the elves to perform menial tasks with no assistance.
Kael'thas, left to his own devices, was offered help from the naga by Lady Vashj
. Given that he was left with no other resources to work with, he accepted her help, repairing several arcane observatories in the area via boats that the naga had loaned him. When Garithos caught wind of this, he was furious. All but calling Kael'thas a traitor, he told the blood elf in no uncertain terms that contacting the naga again would be enough proof to charge him with treason. He then left Kael'thas and the blood elves to fight Scourge forces to the west and promptly took all support, cavalry, and siege units with him, leaving the elves with no support.
When Vashj appeared again, Kael was uncertain about taking her help. But as the only other option was certain death, he agreed to ally with her once more. It was after the Scourge had been successfully driven back that the two spoke, and Kael'thas mentioned the odd fatigue and emptiness within him and his people -- a fatigue he'd noticed ever since the Sunwell's destruction. Vashj told him that much like her own kind, the blood elves were addicted to magic and without the Sunwell to supply them with it, his people would surely die off, one by one. Kael'thas was shocked, but interrupted by the return of the Grand Marshal. Kael'thas told Vashj to flee, but Garithos' men saw the naga fleeing, and Kael and the blood elves were promptly arrested for treason and thrown into the dungeons of Dalaran to await, Garithos smugly informed him, their death sentence.
Vashj came to Kael'thas in the dungeons and offered to help him escape, telling him of her master, Illidan Stormrage
. Illidan, Vashj explained, was a creature of immense power and could perhaps find a way to cure the blood elves of their fatal addiction. After fighting their way out of the dungeons, Kael'thas and his people (along with Lady Vashj and her naga) fled through the portal that Archimonde
had used to enter Azeroth, emerging on the other side in Outland. After helping Illidan escape from the night elf Maiev Shadowsong
, Kael asked him about a possible cure.