The steriotypical Vampire-Werewolf war is not as true as it may seem.
To understand it in full, you need to search for three lifetimes and travel back in time to restore key documents before you would have the base of the truth.
As much as I know it runs as such. Vampires and werewolfs originate from one entity who is often referred to as a Lycan. (I might have the term wrong. This has also been used to refer to werewolves.) The Lycan had two sons, and this is the myth, the first son went out and was bit by a bat, thus he took on the night with hightened senses and drank blood for life.
The second son went out and was bitten by a wolf, thus he became as an animal, bent on death and destruction wherever he may go.
As the sons travel, they took to focusing on humans for victims. The bat-bitten son drank from the veins in the neck, and unless the bodies were destroyed, the humans would turn, becoming vampire in themselves. The wolf-bitten son, did not care for such details. He just went on, attacking anyone in his path, but it seemed that his victims turned as well, becoming as wild and dangerous as he. Thus becoming werewolves.
The vampire clan knew the werewolf was too dangerous, thus they sought him out, burning any bodies they saw on the path. The werewolves had enough human left in them to realize that the vampires were the biggest threat to them, thus they focused on them as what to kill.
The father was horrified at how his sons were warring. He hunted them out and found them at each others throat. He knew he was the only one with the power to stop them, and to kill them would turn all those bit back into humans. But they were his sons and he couldn't bring himself to do so. Instead, he locked them away in unknown coverns for all time.
The minions who were turned continued to roam, turning others. But the third generations were not as the second. The vampires had more weaknesses and the werewolves were human in the daylight.
This is the tale as far as I have gathered.
