Being unable to die converts memory into a burden: the deathless figure accumulates every loss, betrayal, and atrocity he lives through while others are released by dying. Longevity here is not reward but sentence, because the price of outlasting everyone is carrying the full weight of what you have seen.
Grand historical events (slave rebellions, prison tyranny, wartime trenches) are retold from the vantage of the crushed and expendable rather than the rulers who are named in records. Shifting the point of view to the forgotten participant exposes the cruelty that official accounts smooth over.
Oppressive order is sustained less by the tyrant's own force than by the terror he instills in subordinates, who then police each other to survive. The structure holds because victims are made complicit in guarding the very system that degrades them.