Watch our new video "Lament of the Highborne"

The exact origins of "Lament of the Highborne" have been lost to antiquity. Certainly the melody pre-dates the War of the Ancients, in which the song served as a lament for the fallen: a tribute to their steadfast bravery against overwhelming odds. Millennia later, the high elves of Quel'Thalas sang the lament, largely unaltered, in the Troll Wars. Here, too, the elves ultimately proved victorious, but they would not remain so. A plague of undeath swept through the human nation of Lordaeron in the Third War and converted many citizens into mindless undead minions of the Lich King. This army--the Scourge--invaded elven lands and decimated the populace, some of whom were raised into undeath and forced to join the Scourge.

As leader of the last elven defenders, Sylvanas Windrunner suffered a terrible fate: her spirit was ripped from her body and transformed into a banshee. When the Lich King's power faltered, however, she and other undead were freed of Scourge control. She has since reclaimed her body and become queen of these undead rebels, the Forsaken. Although her heart is full of bitterness, she cannot forget the people she once loved... the kingdom she gave her life to defend.

Click here to watch our new World of Warcraft gameplay video of Lady Sylvanas singing "Lament of the Highborne," a sad, ancient elven song of bravery against overwhelming odds:
http://www.worldofwarcraft.com/downloads/movies.html#lament

The term "sin'dorei" has indeed only recently come into popular use as the designation for blood elves. That is not, however, to say that the term has never been used before. On the contrary, like "quel'dorei", it was originally a Darnassian term.

"Sin'dorei" literally translates to "people of the blood" or "children of the bloodline", depending on context. Long before the War of the Ancients, night elf nobility frequently made strategic marriages in order to maximize the magical ability of their children. Over generations, the highest caste in particular set itself apart from the rest of the night elf people. These nobles took great pride in their lineage and therefore used "sin'dorei" occasionally and informally to refer to one another.

During Queen Azshara's reign, however, the arrogance and decadence of these high-ranking nobles reached new heights, and they began calling one another "quel'dorei", or "children of noble birth" (i.e., the Highborne). As a member of this caste, the queen approved of this new name and made it official. Later, after the Highborne were exiled from night elf society, they crossed the sea and continued calling themselves "quel'dorei". Other races tended to refer to them as "high elves". The elves still occasionally called one another "sin'dorei", too: they still took pride in their bloodlines, and "sin'dorei" hadn't lost its meaning any more than "quel'dorei" had. ;)

Keep in mind also that the song predates the War of the Ancients (over ten thousand years ago). Such songs aren't static: they change with the times. The elves have altered the song's lyrics a bit over the millennia to suit the situation. The intent behind the song has certainly changed as well. That is why the song's most recent incarnation so strongly evokes the recent Scourge invasion of Quel'Thalas.