History of Shadowdale - The Fall of Azmaer, Last Drow Marshall of the Twisted Tower
The drow rule of Shadowdale lasted until the early 900s Dale Reckoning, when the increased human population in the area brought the dark elves into conflict with their now more numerous neighbors. The humans were the Dalesmen who a millennium earlier had crossed the Dragon Reach and made peace with the elves of Myth Drannor, settling at the borders of the great woods that was the elven home. The drow soon found themselves under continual attack, and most of those who held overground settlements retreated back below.
The last powerful drow leader was Azmaer, the marshal of the Twisted Tower in its last drow-held days. Azmaer oversaw the last retreat of the drow holdings in the face of a human uprising, and held the citadel against a year-long siege. With supplies and slaves brought up from the Underdark directly into the tower, the drow could have conceivably held out forever; However, a human slave (family histories in the Dales indicate a number of possible individuals) poisoned the well in the Tower and the citadel was easily overrun.
Azmaer's body was not found among the dead, leading some to believe that he escaped back into the depths to rejoin his people. Noting the fact that he would have had to explain to his matriarch how he lost Shadowdale, it is much more likely that, should Azmaer have survived, he went into voluntary exile, hiding from both human and drow. Given that this occurred only 400 years ago, it is certainly possible that Azmaer still lives.