A warlock of one of the highest orders, Jarethan was born far before the age of the Guardians came to an end. Jarethan was schooled in arcane magics at a young age with many of his kin, but soon had a special talent for the manipulation of demonic energies. One of his most bold missions was almost to single handedly march to Deatholme where he personally vanquished the traitorous Dar'Khan Drathir who was responsible for betraying the then High Elven lands to the Scourge during the third war.
Jarethan is quiet in that he spends most of his time in his tower not far from Silvermoon, experimenting with more demonic magics. When the Convocation approached him requesting his services in the field of demonology, he accepted hoping that the Convocation would bestow more knowledge to him. The Naaru emissary from the Convocation, Va'nyu met with Jarethan and instructed him to collect and document as many demons as he could.
Ever since, Jarethan has focused more effort on cataloging his information in the form of a vast library of tomes, with each being copied over and over for distribution. The Convocation has stated that it doesn't care if the knowledge is shared, only that there is that knowledge within its archives and stored.