What exactly is a pureblood vampire? I never fully understood what Valerica meant when she called my character a half-blood in Skyrim.

To be pureblood do you have to be given the gift of vampirism by Molag himself or can you simply be born a pureblood by having two vampiric parents?

I have yet to play the DLC yet, but I think its safe to assume that yes, a 'pureblood' vampire would be one that needed to be touched by Bal himself, or otherwise magical means, where as 'halfbloods' are ones who were a victim of another vampire.

So you couldn't be birthed by vampiric parents and receive the pureblood title?

It would depend on whether or not "pureblood" vampires can reproduce at all.
There is only one instance of a vampire having a child, but it was with a non-infected woman and that vampire was not likely "pureblood."

We only have evidence of one vampire baby ever being born and one of the parents was alive. I don't know how one living and one dead person could have made a baby, but I'm pretty sure that two dead people could not make one.

Even if two undead could reproduce, there would be the little issue of not being able to age. If the child could grow old, they'd hardly be considered undead.

I don't think that could have been any closer.

Ah, I see. I'll have to re-vamp an old fan-fic of mine.

Is there more lore concerning vampires other than in-game books and dialogue such as Immortal Blood or Opusculus Lamae Bal? I've read nearly everything about them in the TES world.

Have you looked into Morrowind's vampire clans?

I found a http://www.imperial-library.info/content/vampires-iliac-bay.

No, "pureblood" refers to one who's turned into a vampire directly by Molag Bal, like Lamae Beolfag.

To note, the baby wasn't a vampire, and it was the mother that was alive.

He was half vampire. I don't understand why you assume he didn't adopt any of his father's traits.

Who knows? If the vampiric made a pact with Molag Bal to reproduce vampiric children, it could be possible. It wouldn't be far fetched for Molag Bal to perform the ritual on an already pregnant vampire.

He had slightly pale skin. I'm not aware of anything that says he was undead, needed to feed on blood, was un-aging, or had any other vampiric trait (though it has been a while since I last played Oblivion, and even longer since I did his quest).

He had slightly better fighting skills then most. Unnatural according to some, but that's it. A pale and strong warrior but nothing that would make people think of him as a vampire.

Interesting to note however is that his father had been married to another woman according to the Gray Prince, yet that woman never fell pregnant and he had been a vampire for 200 years so he likely had six a few more times and nobody else fell pregnant.

Thank you all very much. You've all been very helpful.

Are you sure that was true?

"Lady Lovidicus was a shrew of a woman. The Lord and my mother grew close, and ultimately fell in love. I was the result of their union. When the Lady learned of my birth she was furious, and threatened to kill both my mother and me. So we fled, leaving my claim to nobility behind."

I think his mother lied to him by fabricated an altered account of what actually happened. The mother fled because her lover was a vampire and Lord Lovidicus makes no mention of other women in his journal, or no mention of a jealous wife either.

True it is possible that the mother made an altered account. Still a noble from Cyrodiil, who is obviously important has lived for 200 years and has not married at least once nor had six while he obviously still can and has the urges for six? That's just strange.