Salmissra is the shared name a number of fictional characters in the works of David Eddings, including The Belgariad and The Malloreon. She is both the queen of Nyissa and the high priestess of their god, Issa. The original Salmissra lived during the first age, and was beloved of the god Issa. When she died, each successive ruler of Nyissa was chosen based on their appearance and mannerisms as compared to the real Salmissra. Belgarath remarks that such an arrangement makes things easier because each Salmissra is always the same over the eons. Chosen at a young age, the Salmissras were kept on many drugs intended to keep the appearance of youth but at the cost of violent mood swings and increased sexual appetites. She is attended on by a succession of consorts and eunuchs. The most prominent eunuch in the books is Sadi.
One Salmissra made a deal with Torak to murder the family of Gorek, the Rivan King. This action led to the Alorns invading Nyissa. Centuries later, Chamdar offered another Salmissra immortallity as the Bride of Torak, but Polgara intervened. Polgara helped this Salmissa break the hold various drugs had on her and actually rule Nyissa justly.
During The Belgariad Garion and his friends trail Zedar to Nyissa, where Garion is kidnapped and taken to the most recent Salmissra's palace, where she (being manipulated by Zedar) begins to seduce him. This Salmissra's goal is to present herself to Torak as his bride, and achieve in actuallity the immortallity her dynasty pretends to. To prevent his escape she poisons Garion; but, he is saved when Polgara, with the aid of the Voice of the Prophecy of Light, intervenes. During the confrontation Issa awoke, and Polgara told the sleeping god that this Salmissra was not the same woman he had loved centuries before.
As punishment for her interference and aid to Zedar, Polgara turned Salmissra into a snake with eternal life. Although enraged at first, the snake--still acting as queen--eventually comes to accept the transformation and eventually thanked Polgara in The Malloreon.
"Your passions are also cold, and you can't know how much the body can be used to enslave the will. I'll put his mind to sleep and then smother his will with love." -Queen of Sorcery