You have criticized Tywin on numerous occasions of “breaking one of the oldest Westerosi taboos” which is slavery. Now I hate to nitpick on this issue because I am no expert in this matter but isn’t what he did in Harrenhal a form of state bondage in a time of war rather than actual slavery? Weren’t the captives at Harrenhal technically POWs? And usually in any war, don’t captured prisoners (whether they are enemy soldiers or civilians) get conscripted into doing forced labor without pay and had few if any rights at all during their time of involuntary servitude?
I don’t really see a distinction between “state bondage in a time of war” and “actual slavery,” I guess. At the end of the day, it’s still involuntary labor extracted through force and threat of force.
POW status is usually reserved for enemy soldiers, not civilians, and the taking of large numbers of civilian prisoners is highly unusual. And there really is no precedent for this in previous Westerosi wars – we’ve seen attacks on civilian populations before, but we haven’t seen peasants kidnapped and forced into servitude before.
The only thing that comes close is “Lord Lymond Hightower, the Sea Lion, who revived the practice of thralldom in Oldtown just long enough to set the ironmen captured during the battle to hard labor strengthening the city’s walls.” But even then, that’s enemy soldiers and temporary.