Chaos Unit Recruitment

[AgrippaDaRippa]

I know that in the actual universe (lets just assume in the books it was all Chaos Undivided) many Norscans and the occasionals of other races would flock to join the Chaos and were given mutations and weapons as gifts for fighting well from the Gods....

In the campaign walkthrough they seemed a little iffy on how recruitment would work for Chaos.

This may have been pinpointed in the video but I watched it a few times and didn't catch it. If somebody would like to point out to me when they explained it in the video or if they didn't I would like possible ways it will work.
I think that it may have been sort of implied that you recruit from the warbands traveling cities but I am not sure.

[craziii]

they work like the hunts from attila. you also get region specific units when you liberate(check the total war official youtube channel, the newest video shows how it is done) or whatever it is you do as chaos. you unlock units by building your the required buildings and be in a region that has it after you liberate it.