I work in a museum, where I research a particular period of history and run seminars that pertain to it. Yet as an institution, historical museums seem to be fairly recent things! When did people first start curating artefacts and displaying them for the general public? When did people first start organising educational tours around such exhibits? In short, when and where did historical museums first come into existence, and why?
Note: I'm referring to these as "historical museums" in deliberate contrast to art galleries. I think that the history of the art gallery is also an interesting question, but it's a separate one, and since artworks possess a more readily identifiable aesthetic value, my guess is that they would be of greater antiquity.