h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Not sure if we have that much detail around here. There has been a census every decade since 1971, but data protection regulations prevent you from getting individual data (most data is statistical anyway).

Yes, here the individual data isn't usually released until 100 years has passed, so it is unusual that the 1939 data is available already. The data relating to people who are still alive has been redacted, though.

One big thing that has been in the news recently is that a large archive will be made public which can tell if somebody was a collaborator in the Second World War. This sparkes some controversy as to whether people would get backlash if their parents were 'bad'.