The Red Wizards are an organization of wizards in Faerûn. During their height of power, the Red Wizards were the notorious and nefarious spellcasting ruling class of the inhospitable but well-inhabited country of Thay. Slavers, demonologists, and magical experimenters, the Red Wizards were much feared by most of Faerûn. They constantly schemed to bring down their neighboring nations of Rashemen, where they were thwarted by the equally famed magicians the Witches of Rashemen, Aglarond, where they were turned back by the Simbul of the Seven Sisters, and Mulhorand, where the people of Thay first emigrated from.
The leaders of the Red Wizards, and of Thay, were the eight zulkirs, each for a different school of magic. Chief amongst these, and, indeed, among all Red Wizards was Szass Tam, a powerful archmage and feared lich and now the ruler of Thay. Since Szass Tam’s takeover, the Red Wizards have transformed enormously, becoming a loosely organized chain of merchant enclaves who specialized in procuring magical items.
After another failed attempt at securing Rashemen in 1357 DR, the Red Wizards planned to infiltrate the nations of Faerûn legitimately — in Thayan enclaves which would publicly sell magic items and quietly also traffic drugs, wicked spells, and slaves. Using these they hoped to eventually have strongholds and resulting political infiltration that would make them indispensable and powerful, and eventually get them something along the lines of world domination.
Despite the general distrust and dislike that most felt towards the Red Wizards, the mages were still able to extend their power to almost every corner of the Realms, running their enclaves as planned in towns where slaving was otherwise banned. From here they ran a lucrative business in the trade of magical items, spells and artifacts, making them virtually indispensable to many of their clients, and as such the wizards expanded their sphere of influence ever further.