The Hall of Jörmungandr – and, by extension, the whole Setite population of Scandinavia – descends from a single vampire, Arnulf Jörmungandrsson, a former merchant that returned to his home after having converted to the teachings of Set on a trip to Egypt, where he was granted the Embrace. He first attempted to build a cult centered around the serpent Nidhöggr, who gnaws at the roots of the World Ash. He let that fail when he ran across another cult dedicated to the dark serpent Jörmungandr, and that immediately eliminated their competitors for their master's favor. After that, Arnulf resorted the other great serpent of the mythologies of the High North, but Jörmungandr was exactly the kind of deity that encouraged an active worship. Still, the Hall of Jörmungandr gathered its followers, mostly retired Vikings who had plundered themselves enough riches that they could live without seafaring anymore.
During the Ismaili Revolution in the middle of the tenth century and the establishment of the Fatimid dynasty, the Hall was severed from contact with the Egyptian main Clan and continued to prosper in hiding, amassing fortune and resources. By the time of the 18th century most Kindred had forgotten the true nature of Arnulf followers, regarding them as Toreador. In the 19th century, Arnulf, who had even risen to primogency within Oslo, played patron to nationalist Norwegian artists such as Edvard Grieg, and the "Hall of Jörmungandr" became a fashionably naughty night spot for artists, folklore enthusiasts, and assorted poseurs.