There's heated debate around whether people who did terrible things in the past, at a time when there was widespread acceptance of such actions, are appropriately blamed by us, on the grounds they weren't really morally ignorant, or their ignorance was itself culpable. I point to puzzles that arise if we blame them. We need to explain how they could act so badly if they weren't fully ignorant. I argue that plausible answers to that question entail that they're not blameworthy, or that we lack standing to blame them.