The Tel'Quessir races are not native to Faerûn. They come from the plane of Feywild, twenty-five millenia ago. The first wave of Tel'Quessir to arrive were the green elves, the lythari, and the avariel. The dark elves arrived in the second wave of emigration, along with the sun elves and moon elves. Later, the aquatic elves appeared in the Great Sea. Dark elves are by far the most successful of these Eladrin emigrants. They settled into two major eladrin nations. Miyeritar was located in what is now the High Moor, and consisted primarily of green elves and dark elves. Ilythiir was an eladrin realm of predominantly dark elves, and they lived farther south-east. Dark elves also come from the Underdark. In 1374 DR, Khelben Arunsun brought together many powerful mages to restore life to a lost city known as the Hidden City of Hope.
Drow society is matriarchal, militaristic, and heavily influenced by religion. Their city-states are built in humongous underground cave systems but are constantly at war with each other. These cities are ruled by the most powerful of the families (or houses) and although the power of the many families changes often, the top few usually remain stable. Males who hope to find any place of power in society often resort to ends as treacherous as the women that rule the drow, hoping to perhaps win a coveted place as the Mate of a powerful matron mother.
It can be easily imagined that female drow have it much easier but this is simply an illusion. Their prestigious position within society comes at a high cost. In fact the teaching of Lolth, and drive to receive more power and competition between females, mostly those who belong in houses are so violently competitive that the males do not have to deal with them. Matters are even worse for those who seek power through venues outside of Lolth’s church, where the females have to compete not only with one another but with resentful and oppressed males.
Behavior of a drow are ambition, arrogant, treacherous, hedonistic and sadistic. At birth, drow are taught that they are much more superior than other races and to crush those beneath them. Young drow that show loving or kindness are brutally punished, this drives the cruelty into them. They value advancement over their peers more than anything else, pulling down their superiors and crushing their inferiors. This does not mean they treat all peers with disdain, however. Drow appreciate a sense of stealth and thus drow are often urbane and courteous, even to dangerous rivals.
Cities are set up around the most powerful families claiming the greatest areas, this leaves the other drow with whatever land remains. The focus of a city is often the temple of Lolth and this is often in the grounds of the ruling family. Magic items that emit faerie fire adorning buildings are a sign of prosperity. On the outside of the city is the garrison and some of the slaves. Rothé farms are also outside the city.
Often, a city will seek to forge an alliance with powerful Underdark creatures, such as a deep dragon or a beholder so they can can receive extra protection.
Drow who live on the surface do not form any kind of organized society and instead live as hermits and outcasts. They will interact with other societies when they need to, but not through choice.
Toxins and poisons are favored by drow, especially a special slumber potion made from a black fungus growing in the Underdark. Other poisons can be made by scoprions, purple worms and spiders.
When crafting armor, the drow prefer mithral chain armor when it is possible to get. They wear non-restrictive armor that will not affect their natural dexterity. Certain weapons are favored by drow, such as rapiers or hand crossbows. They use the hand crossbows to deliver their poisons from a distance.
It is common for drow to place magic symbols or glyphs outside their houses which can ward against intrusion. These house defense glyphs are only one of the three types of glyphs, the others are way-marker runes and sacred glyphs.
The drow love magical items of all kinds and all powerful families give some enchanted items to those who service them. The piwafwi is a particularly special drow item, although the drow house insignias are also important to the drow houses and grant special powers, occasionally levitation. Many drow items are crafted in such a way that they can only be used by the drow.
Drow primarily worship the Dark Seldarine, that is, those deities cast out of the Seldarine and exiled to the Demonweb Pits. They generally worship the goddess Lolth although those on the surface often worship Vhaeraun or Shar. A small number of good drow on the surface worship Eilistraee or other non-drow pantheon deities and are lead by Qilue Veladorn. Generally an entire city worships a single deity. Even more of a minority are the drow that worship Kiaransalee and Ghaunadaur. Also, because drow males are banned from the priesthood, males who become adept in divine magic tend to worship Selvetarm, Lolth’s champion.
Though religion plays a large part in drow society, the caste system and other seemingly-lawful aspects of the culture clash with Lolth’s intent and directives as a chaotic evil goddess. As a result, much of the tension between the clergy of Lolth and more secular drow comes from this very different perspective.
Parts of the Magic & Faith section were copied from Forgotten Realms Wiki. Give them the credit!