The first war the world ever knew was so great, so horrific, that it literally destroyed the world.
Fallout included the creation of the various parallel worlds the Seven PeoplesThe Seven Peoples of the Earth are the seven identifying categories applied to most sentient beings in the world. More occupy. The last ice age? Due to the war. Earthquakes splitting up continents? Due to the war.
NotteHe’s one of the oldest living beings among the Mythos. The father of all vampires (or Night-Children, as they’re called),... More was one of the handful few who survived it, called OriginalThe Originals are the few beings who survived the First War, and were responsible for essentially rebuilding society among all..., and it has a marked effect on the way he relates to other living beings.