The 2000 Year Epic Campaign
The Emerald Circle rose from the ashes of the Emerald Viper Clan, a human tribe from the Jayt Valley of the 1st Era. The Emerald Viper Clan lived in the Aradesh Desert where they were quickly taken over by the Spirit Naga, Merrshaulk and forced to serve her as she transformed them into yuan-ti. After the Champions of Elon slew (for the time being) Merrshaulk, it freed the citizens of Sahjar from this eternal slavery.
Transition from 2nd to 3rd Era – Having the ultimate do-over, the remaining members of the Emerald Vipers swore off their snake roots and formed the Emerald Circle, and actively work against Merrshaulk. While they have had no success against her in the Mausoleum of Merrshaulk, they have attacked her new followers, the Followers of the Scourge wherever they can find them throughout Brind-Amor.