The barbarian in the second lesson of the practical course- is he part of a barbarian invasion in the Dark Ages and plundering the farmer, is he part of the ruling elite in a nomad-ruled kingdom and taking advantage of his power, or is he just some guy, and the farmer helps him out simply because religion and tradition in the Plain demand it?
Since these are isolated examples, they don't really have a backstory. However, he's alone, so he's not likely to be part of an invasion. Barbarians do wander into Eretald for trade, or even to briefly take jobs.
