Introduction and History
Ten thousand years ago, during the reign of the Night Elf Queen Azshara, there was an elite magic-using sect known as the Highborne, who dabbled in magics that many other Elves considered heretical by drawing upon the power of the Well of Eternity. Several centuries after the Sundering, which destroyed the Well of Eternity, the Highborne left Kalimdor and settled on the Eastern Continent, founding the kingdom of Quel'Thalas. They became known as the High Elves. During this time, they created the Sunwell, and switched to a diurnal waking cycle, instead of the nocturnal cycle they had kept when they were Night Elves. Their purple skin eventually faded to a pale peach color, like that of the Humans and dwarves.
The High Elves assisted the Alliance of Lordaeron in the Second War against the Horde and in the war against the Burning Legion. During the Third War, however, Prince Arthas led his army of the Undead against them, ravaging Quel'Thalas and corrupting the Sunwell. The High Elves were nearly wiped out in the conflict. In remembrance of their fallen brethren, most of them renamed themselves the Blood Elves, or Sin'Dorei, and swore to avenge their fallen race.
Cut off from their source of power once again, the Elves went into magic withdrawal. Desperate for aid following the Third War, the Blood Elves accepted help from the naga. This was seen as treachery by the Alliance and they were sentenced to death. Prince Kael'thas Sunstrider led his followers to freedom, to the extra dimensional wastes of Outland, the remnants of Draenor, to pledge allegiance to Illidan who promised to grant them a new source of magic by siphoning the chaotic energies of demons. Together with their allies the naga, Illidan led the blood elves to conquer Outland, gaining in the process the friendship of the nearly extinct draenei.
The Blood Elves then followed Illidan to the Icecrown Glacier in an attempt to destroy the Lich King, however, their plans were foiled by Arthas who wounded Illidan forcing the allied Blood Elves and naga to retreat, allowing Arthas to ascend the glacier and merge with the Lich King.
According to the Alliance Player's Guide, Alliance & Horde Compendium, and World of Warcraft RPG, High Elves and Blood Elves look similar in nature, usually having blue, green or white eyes (though High Elven eyes do not always glow). In World of Warcraft, High elves tend to have blue eyes, white to light blond hair, and appear more pale and sickly in nature compared to the models of the Blood Elves. Blood Elves tend to have more reddish-tinged skin, and crimson or violet-colored eyes, as well as usually having more elaborate haircuts.
In the time between the Third War and World of Warcraft, Blood elves began to take up wearing red and black in memorial of their lost empire and brethren. They also adopted hair styles against the norms of their previous High Elf society and painted runes on their bodies to ward off demons or to simply look threatening. Nevertheless when approaching Alliance towns Blood Elves would often disguise themselves as High Elves to avoid harm.
This appears to have changed by the time of World of Warcraft as Blood Elves have begun to show up in Alliance Lands undisguised, sometimes as ambassadors, other times asking for help to collect reagents that they need for spells. Still others attack alliance on sight such as those from the Thalassian Base Camp, and those that have joined the Horde.
- In the Road to Damnation short story, taking place before the destruction of Quel'thalas, Prince Kael'thas is seen in a screenshot using a new blood elf model. This may mean that the blood elves have had no physical alteration since the loss of the Sunwell. The changes in physical appearance, such as the green eyes that were rumored to be caused by fel energies, actually have no lore explanation and are simply the new look blizzard has come up with. Some think that if Kael'thas (who is known as a High Elf at the time) is using the new model, that maybe all the other High Elves will use it also in the coming expansion.
- However, it is also possible that both the High and Blood Elves will use a similar model, but will have different skin colors, and eye colors, much like the current in-game models. The High Elven skin and eye colors will not available to the Blood Elves during the character creation screen (similar to how the Sand Trolls use the similar model as the Jungle Trolls, but have a reddish-pinkish skin color which Jungle Trolls do not).
- It is also possible that the video just uses the unique Kael'thas boss model that will be used in a later dungeon (Tempest Keep) for the scenes, and may not apply to any other current high elves at all. The new model may apply to current Blood Elves in the game, however, which are seen in Aszhara and a few other places. (While Kael'thas is shown to have green eyes in the video, in the other appearances of the character he is shown to have white eyes (e.g in Frozen Throne and other artwork)).
The Burning Crusade
Not all blood elves currently reside in Outland, some have remained in Azeroth. Flushed with their new found power born from their ability to tap into demonic energies from the Twisting Nether, the Blood Elves have managed to retake their beloved land of Quel'Thalas. Silvermoon has been rebuilt and the resident blood elves there plot to return to Outland, where they can reunite with Kael'thas and achieve the golden destiny he promised them.
Unfortunately, the blood elves' practice of embracing demonic energies resulted in them being shunned by their former comrades in the Alliance. Thus, the remaining blood elves on Azeroth look desperately to the Horde to help them reach Outland. The orcs are wary of accepting them, but the tactical advantage the of Blood Knights is a huge buff for the horde forces. It is unknown what relation Sylvanas Windrunner, leader of the Forsaken, will have to the blood elves. At E3 the blood elves had no Towns/Undercity reputation bar on their reputation tab, so blood elves may only tolerate the forsaken and not be able to raise reputation with them. A lot of the forsaken would have been involved in the siege on Quel'thalas, which could explain a possible distrust between the two races.
The blood elf languages will be Sindassi and Orcish, and they will be able to pick the Classes/Hunter, Classes/Priest, Classes/Warlock, Classes/Rogue, Classes/Mage and Classes/Paladin classes, according to an update on the official homepage. This seems to be the final outcome, and it is likely it will not change any more after such an announcement.
Leadership in Quel'Thalas
Lor'themar Theron, Regent of Quel'Thalas: Leader of the Blood Elves on Azeroth in the Prince's absence
Grand Magister Rommath : Leader of all Blood Elf Magi on Azeroth, and a fiercely loyal servant of Kael'thas
Halduron Brightwing : Ranger-General of Silvermoon, the blood elves' military commander on Azeroth
Since the destruction of the Sunwell at the hands of Arthas and the Scourge, the Blood Elves have been forced to deal with the sudden relapse of their addiction to arcane energy. A constant curse since the original Well of Eternity was destroyed, the addiction has become more powerful than ever. Blood Elves spend their waking days struggling with their weakness, seeking either to sate it by siphoning magical energy from their surroundings or to resist the urge to feed.
While the Blood Elves do not abstain from draining arcane power directly, they are careful to keep their addictions under control, keeping the power their new abilities offer while maintaining self-discipline. Those who lose control over their addiction are known as "the Winnowed," and invariably fall into insanity and corruption.
As Arcanist Helion (a starting zone quest NPC) says, "Control your thirst for magic...It is a thirst unending." 
Blood Elves wear crimson-colored robes to suggest their fiery affiliation and the blood of the fallen Elves in Quel'thalas. Many concentrate on studying arcane and fire magic, as opposed to the traditional frost and water spells of their lost high elf society.
Blood Elf architecture is breathtaking. It involves pendulous creations of wonderous curves and columns, its designs natural, floral, flowing, animal. Their fountains seem to defy physical boundaries, creating or warping water in impossible ways.
Blood Elves have flags that feature a phoenix. In the Third War, Blood Mages had the ability to call phoenixes from the Elemental Plane of fire. These creatures appear to be deeply connected with the Blood Elves, possibly because they share a destructive nature, or perhaps due to their purely magical composition. This could allow the Blood Elves to have increased control over them. Since the phoenix dies and becomes reborn, it could be a symbol for the Blood Elves - the Blood Elves metaphorically 'died' as High Elves and were reborn as Blood Elves.
The Blood Elves were formerly known as High Elves, before the Undead Scourge's attack on Quel'Thalas. Following the Scourge's invasion, Kael'thas decided to rename his people as Blood Elves, to honor their brethren who had fallen in battle against the Scourge.
The Blood Elves are constantly threatened by the Wretched, who are devolved Blood Elves who lost much of their sanity. Their ancestral homeland of Quel'Thalas also borders the Deatholme region, which has been heavily infested by the remnants of the Scourge that occupied Quel'Thalas. One faction, named Tranquillien, consists of Blood Elves who wish to purify the region of the Undead.
From Blood Elf and Draenei Racial Abilities (Bluetracker copy), posted by Drysc:
Since our showing at E3, we have seen many threads and articles discussing the Blood Elf and draenei racial abilities, and were happy to see so many players excited about these two new races! In some cases these conversations have included misinterpreted or otherwise incorrect statements of the abilities of these two new races. Below we have listed the abilities that were shown at E3 for both the Blood Elf and Draenei.
Please keep in mind that these abilities may change before the release of The Burning Crusade expansion.
Blood Elf characters can play as the following classes: 
- Classes/Paladin (Also referred to as Blood Knights)
- Recently announced is the addition of the Paladin class to the Blood Elves thus allowing the Horde to play the Paladin class.
- News: The official list of classes available to Draenei and Blood Elves has been released. The only change was that blood elves will have access to the Hunter class rather than Warrior, making it the only race in WoW to not have Warrior as a racial class. See .
- History of the Blood Elves
- Official page for further information about Blood Elves, which is the new Horde race in The Burning Crusade
- Official History of the Blood Elves
- Rise of the Blood Elves, from the History of Warcraft
- Blood elf units in Warcraft III