Edyrem is the label given to Uldyssian's followers. The word means "those who have seen"<ref>Scales of the Serpent, page 62. Richard A. Knaak, 2007.</ref> which is quite fitting considering their natural affinity for magic has been awakened within them. The Edyrem are simply Nephalem and were considered normal people until Uldyssian converted them. Uldyssian awakened their power and fought beside them in the Sin War. The main goal of the Edyrem was to bring down the cults of the Triune and Cathedral of Light. In the process of doing so the Edyrem killed Lilith, Lucion, the false prophet Inarius, countless Peace Warders, Inquisitors and even some brainwashed farmers.
The Edyrem gather recruits as Uldyssian journeys to cities and awakens the magic within each person. Because of that fact, the Edyrem originate from many different cities including Seram, Partha, Toraja, or Hashir.
Scales of the Serpent, page 62. Richard A. Knaak, 2007.