Often called the “dark elves,” the drow are actually five different cultures:

The giants of Xen’drik were an advanced race, with all the trappings of powerful arcane magics and an elaborate civilized infrastructure. With any such affluence, there comes a desire from the affluent to have someone do their menial labor. Several attempts had been made to collect servants; goliaths became weak and ineffectual when taken into captivity, sahuagin were too wild and bound to the sea, and thri-kreen had trouble understanding abstract concepts. When the giants of the Cul’sir nation found the eladrin feyspire tens of thousands of years ago, they were fascinated by the small, yet seemingly magical creatures. Instinctively, eladrin could adapt to natural conditions and used arcane energies intuitively, showing an intelligence at least close to that of a giant child. After the top wizards determined the pattern of the spire’s appearance, they assembled a strike squad around the spire and invaded. Although the spire’s occupants did not go softly, the outcome was inevitable. Soon the eladrin were shipped to the four corners of the continent, and local giants adapted them to their needs. Soon, though, the resistance and restlessness of the new slaves became a problem.

As the eladrin reacted to Eberron’s arcane and primal energies, they became what we know today as elves, and a new aggressive nature was born out of this evolution and their captivity. Sometimes, this aggression was physical, coming into the world as military rebellions. Although the giants were able to squash these rebellions easily enough, it was still a waste of their precious time and resources. So they turned to their most advanced masters of biomancy, giants who wove genetics and magic together (a precedent for House Vadalis’ techniques). The biomancers gathered several bloodlines of elf and began experimenting. After a few decades, the giants realized they could not breed obedience into the elves, but they could give them powers abhorrent to their race, making them outsiders. This new outsider class would serves as the “house slaves” to the elven “field slave.” Experiments were made with Xoriat technology, but the results were too dangerous (even today, a tribe of aberrant elves roam the tundra of Xen’drik). A simpler solution of binding dark magic to the elves’ souls created the drow race.

Soon, drow became a epithet in the elven tongue, as they watched former brothers become the right-hand servants of the giants. There was nothing inherently evil about the drow, but too many of them allowed themselves to be tempted by dark arts and the praise of their gigantic masters, and the reputation carried to every dark-skinned drow. As most of giant civilization laid in jungle, the drow were built for humid, dense forest. A few offshoots were also created. Feskano drow manned the ships of the Cul’sir trading network, webbed feet allowing them to swim alongside the boat. Tiran drow braved the volcanic fields and tundra to find dragonshards and fight off invading demonic hordes from Everice, thick skin and fur protecting them from the elements. These wild places made their drow wild and rare. But there were also places where drow culture grew strong and bound together, like the haratana.

Today, most people who encounter drow know them as visitors or guides in the city of Stormreach, mostly from Vulkoori tribes (with the occasional Umbragen coming from underground). The other cultures stay mostly hidden or so far from civilization that they might as well be.