User blog comment:Jannism/Half-Troll origins/@comment-25225066-20141118205537

I disagree. If they were two different things bred together, they were probably bred by someone. But they are wild and do not really serve anyone like the orcs and Uruk-hai do. So I would guess they are some type of Far Haradrim that just became more wild. There is no way to be sure though.