Vampires are spread out all across Cyrodiil. While individual vampires are known to be created through infection by the disease Porphyric Hemophilia, the origin of the species as a whole is largely unknown. According to a tome in The Vile Lair, vampires are the indirect creation of the Daedric Prince Molag Bal. 
Vampirism is the result of Porphyric Hemophilia, which can infect humans, Mer and even Argonians. Thus, vampires are not strictly a race themselves, but rather are vampiric forms of nearly all other sentient races. As a result of their transformation, a vampire's skin becomes pale or gray-tinted, their eyes turn red (or white in the case of Khajiit and Argonians), and their canines sharpen into fangs. Most vampires, however, can suppress this transformation through the consumption of blood, which allows them to coexist with the mortal races.
Vampires are physically superior to humans, having improved strength and speed, and inherent invisibility and charm powers. They are also immortal, and cannot be killed through starvation or old age. They are greatly affected by the former, however, which the Hero can see at a few points throughout Cyrodiil; decades of starvation will drive vampires mad, and they will go feral and attack on sight[source?]. Most notably to the Hero, all vampires can transmit Porphyric Hemophilia in combat, which causes vampirism after three days if left uncured.
They also exhibit many of the weaknesses assigned to their kind in oral traditions; they are all weak to fire, and advanced vampirism leads to weakness to sunlight, hence many vampires choosing to live in dark areas such as caves. However, vampires in Tamriel aren't affected by garlic (with the exception of Vicente Valtieri, who was allergic to it even as a human).
The bulk of the vampires that are encountered across Cyrodiil are vampiric forms of some other character class. Vampires conform strictly to their class, as can be seen by their choices of weapons, magic, and armor in combat. This is particularly handy during the Daedric Quest Hermaeus Mora which requires the player to soul trap all 10 races.
- Vampire Acrobat (Bosmer)
- Vampire Agent (Breton)
- Vampire Assassin (Dumner)
- Vampire Bard (Nord)
- Vampire Barbarian (Nord)
- Vampire Battlemage (Dumner)
- Vampire Crusader (Orsimer)
- Vampire Knight
- Vampire Mage
- Vampire Monk (Imperial)
- Vampire Nightblade
- Vampire Pilgrim
- Vampire Rogue (Redguard)
- Vampire Scout
- Vampire Sorcerer
- Vampire Spellsword
- Vampire Thief
- Vampire Warrior
- Vampire Witchhunter (Altmer)
Vampire Patriarch and MatriarchEdit
Vampire Matriarchs and Vampire Patriarchs are powerful vampires. As their names imply, they are the "mothers" and "fathers" of a band of vampires, similar to a Marauder. Having a high position, they are very well equipped with the highest quality armor and weapons of their level. Use caution, as they defend themselves well, and attack viciously. Like all vampires, they have a weakness to fire.
Matriarchs and Patriarchs can usually be found in caves, Ayleid Ruins, mine, or fort that contain nests of vampires, but not until the higher levels. A large concentration of Vampire Matriarchs can also be found in the plug-in Mehrunes' Razor during the Unearthing Mehrunes' Razor quest. They are likely to carry leveled heavy armor and weapons.
- Barren Cave†
- Bloodcrust Cavern
- Fort Carmala†
- Fort Hastrel
- Fort Redman
- Fort Redwater
- Fort Roebeck
- Fort Vlastarus
- Gutted Mine
- Lipsand Tarn
- Memorial Cave
- Under Bloodworks
† indicates vampire patriarch/matriarch location.
- Pale Lady - In Castle Skingrad's Wine Cellar, through the hidden passage. Killed during the quest Lost Histories.
- Vicente Valtieri - A higher-ranking member of the Dark Brotherhood. After completing all of his assigned contracts, he will offer the Hero the chance to become a vampire, by biting them when they sleep in the Dark Brotherhood sanctuary. He is killed by the Hero during the Purification.
- Janus Hassildor of Skingrad.
- Jakben, Earl of Imbel - Thought to be the last living descendant of the legendary thief Springheel Jak, but upon reading his diary in the family catacombs, it comes to light that Jakben is in fact Springheel Jak, still alive after all these years.
- Lord Lovidicus in Crowhaven. He is the father of Arena Grand Champion, Agronak gro-Malog.
- Seridur - a vampire working from Memorial Cave and member of the Order of the Virtuous Blood.
- Hindaril - An old and powerful vampire whose ashes are needed to create the cure for vampirism.
- It has been suggested that there are over one hundred different kinds of vampire, and that there are nine kinds in the Iliac Bay region alone. Other types of vampire in far-off lands are described in the book Immortal Blood.