A few centuries ago humans went to war with an alien race called Namorns, they look like humans with too-large eyes and hands. Though it didn't last very long there was much bloodshed, way to much. People call it the Great War. After awhile the Great War moved to Yadar and humans and namorns met the lizard people. Now, the Lizard people are pretty peaceful, you leave them alone they'll leave you alone. But the humans and namorns saw the lizard people fight and decided that the lizard people were dangerous and had to be killed before the lizard killed them. So that added more bloodshed.
This really doesn't have to have anything to do with the story, just lets you know what has happened.