[chrispedersen]

if you conquered a territory and got an affliction not obviously caused by being in combat

it is likely that the territory has an inkpot site - (or one of the others) that causes disease.

Alternatively, its winter, you're old, and you just got an old age affliction.

But battle is the most likely reason- there are a few other sites that will do it. Also a few remotely cast spells, if the caster has death can do it as well. But you'd see those. Like seeking arrow if you have a death bless etc.