Recently on Worldbuilding Stack Exchange, somebody asked: what would be the least traumatic way to introduce resurrected historical humans to 21st-century life? The question postulates that, somehow, it has become possible to resurrect everybody who ever lived, and we somehow have places to put all 100 billion or so of them. Some religions have end-times beliefs involving this, but here we're talking about a technological, human-driven act. Ok, so how would one actually go about it so that bronze-age man doesn't get squished in traffic? Or, for that matter, so enlightenment-era man doesn't get squished in traffic? Acclimation is hard.
To the resurrected, the disorientation is akin to that from time-travel. Time-travel into the past is bad enough, with concerns about butterfly effects, preventing your own birth, catching deadly diseases that were wiped out long before you were born, and generally messing up history (or ending up on an alternate timeline when you return). But in principle one can prepare for travel into the past -- study up on it, get the right immunizations before you go, learn the relevant languages, and so on. The future, though, is uncharted territory, and even if you have ideas about how things will go, you're probably going to be surprised and confused, maybe at risk of getting squished in traffic by self-flying cars.
So we need a way to orient the newly-resurrected, who for all practical purposes have travelled in time to our present. How would we do that?
I suggested starting with the most-recently dead and working backwards. Somebody newly-arrived from the middle ages (without an appropriate support structure) will be baffled by the modern world. Somebody who died last year probably won't be. So start by resurrecting the most-recently departed, get them oriented, and then have them help the next class. Iterate until done. If each pair of resurrected and guide only differs by a generation (or less), and they're also matched up based on language, culture, and other factors, then each guide should be able to explain the wonders of the modern world in ways that both he and the resurrected can understand. Somebody from 1800 won't explain cars to someone from 1780 in the same way that we would, but that doesn't matter. Make the gaps small enough and people will be able to bridge them. That was my proposal.
Then Green came along and wrote a much better answer. Green suggests treating resurrection as arrival in the afterlife -- not, strictly speaking, untrue, and many people will already be pre-disposed to believe in such a thing. Before starting the resurrections, modern people have to build places that resemble the afterlives described by various cultures and religions. (Fortunately, we've been told that the problem of where to put all the people is solved, so this just calls for setting up those places in particular ways.) As people are resurrected, assign them to these various "heavens" with other people who share their cultural background and appearance. (Green describes a precedure for interviewing and "decanting" new arrivals to get them to the best destinations.) This approach reduces shock and might be good enough for many people, though it's not full integration into the modern world. Nothing requires that people stay in their heavens, so those who don't like where they emerged can go elsewhere -- maybe even join modern society, for which they'll need a lot of education. But it's optional.
Another user, bio, suggests working through the children, children being more adaptable and faster learners. There will be a lot of them, given historic child-mortality levels. Use that.
Amidst the creativity and fun comes a cautionary note from anon: what about the ethical considerations? By bringing people back, aren't you imposing your own ideologies on them? What if they don't want to be part of your modern world? What if death was an escape for them -- and now you've undone it? What if your actions invalidate their religious beliefs? And what about ideologies that you'd rather stay in the past -- if you resurrect people, you're also resurrecting their ideals, for good or ill. Maybe not everything and everyone should come back -- but as soon as you say that, you have to decide how we decide who gets to live again. That way lies...difficulty.
The Worldbuilding question asks about practical social issues, but it seems like the really tricky and interesting issues are in the realm of ethics. What issues do you see in this scenario? Please use the comments to share your thoughts.