In White Wolf's World of Darkness roleplaying games, Tremere is the public name of a 10th-century magus of the Order of Hermes. He founded a new House of the Order, which took his name. Tremere, together with his closest followers, sought the secrets of immortality after he began to sense a shift in magickal forces away from the Hermetic style. One of Tremere's inner circle, a magus named Goratrix, eventually uncovered a ritual which would confer immortality after experimenting on Tzimisce vampires. There was just one twist: the ritual would also confer the Curse of Caine on the caster. Goratrix took the ritual to his master, who decided that immortality was worth any price, and in the year 1022, Tremere and his seven closest follwers became fourth-generation vampires through this ritual.

In the process, their Avatars were shattered and subsumed into the greater Avatar of Caine, so they lost the ability to work True Magick. Lacking their former magickal might, Tremere and his followers managed to create the incredibly versatile vampiric Discipline of Thaumaturgy, which is strongly rooted in the philosophies and dictates of the Hermetic magickal style.

In the years that followed, Tremere and his followers went forth and turned other members of House Tremere into vampires, while hiding the fact of their undeath from the other Houses of the Order of Hermes. Additionally, Tremere took up the search for the Antediluvians, the semi-mythical progenitors of the thirteen great vampire clans.

Eventually, he located several slumbering Antediluvians, but he selected peace-loving Saulot, the founder of the Salubri clan, thinking Saulot to be an easy mark. (This turned out to be a grave tactical mistake on Tremere's part, but that's another story). Tremere diablerized Saulot, and thus it was that the Tremere replaced the Salubri as one of the great vampire clans. Tremere ordered the eradication of remaining Salubri, so that they would not spread word of Tremere's crime to the rest of Kindred society. To this day, the peaceful Salubri are hunted as soul-devouring infernalists, due to the highly successful Tremere smear campaign.

Of course, the Tremere still labored under intense suspicion. The other vampire clans, particularly the Gangrel, Nosferatu and Tzimisce, attempted to wipe out the Tremere, but thanks to the power and versatility of Thaumaturgy -- and the servants the Tremere created with their powers -- they survived. Also, the Order of Hermes discovered Tremere's deception in the 1200s, and declared a war on the magical vampires which has continued into the 21st century.

Over the centuries, as his Clan fought for power and safety in Kindred society, Tremere Himself eventually slipped into the torpid slumber which plagues all ancient vampires. Rumors spread that his body had lost its original shape, and in the coffin where he once rested lay a strange worm-like creature, pale white and pulsating. Another rumor had it that a third eye appeared in Tremere's forehead after he diablerized Saulot (the third eye being, of course, the trademark of the Salubri clan and its founder). Few outside of Tremere's inner circle were aware of this, but a titanic battle of wills was taking place in Tremere's mind. Tremere had, upon diablerizing Saulot, absorbed a large portion of Saulot's soul along with his power. This soul-shard fought Tremere for control of his body for 800 years, and finally -- in the late 20th century -- Saulot apparently won, cast Tremere out of his own body, and has risen from torpor, directing the activities of Clan Tremere in Tremere's guise and with Tremere's voice. No one knows what has happened to Tremere's soul, of course. It might have found another host-body, or it may have simply disappeared. It is unlikely, however, that such a cunning creature as Tremere would have simply allowed himself to be destroyed.

In summation, Tremere founded the clan of vampires which is, arguably, the most powerful, most dangerous, most cunning and unquestionably most literate in the world. Wouldn't you rather be on his side?