[@Mistress Dizzy] Yeah, the history is that way back the Kree experimented on humans with the aim of having an army. These inhumans have now developed their own (very hierarchical) society. Essentially they're normal humans until they're exposed to the mist upon which they 'skip' a few stages of evolution

They have started to introduce this to the MCU but until the movie is out I'm not sure where they're heading with it so much, so I mostly stuck to the comics :)