It ultimately depends! Languages are definitely gone, but there is a sense that this world used to be a lot more multicultural before everyone was at risk of dying. People know that this was once Earth, but a lot of people feel rapidly and far removed from it.

Some history gets taught in the compulsory schooling before the Cotillion, but it's largely a Great Man style of history, focusing on specific figures (and lessons adjacent to them), rather than anything you'd find today that could be more nuanced. At the heart of it would be this cult of personality around The Conclave-turned-Parliament, since all history seems to oddly go in that direction.

So, there is a vague sense but we're playing fast and loose with it. The AU allows for some blurry lines here given the traumatic event, so let us know if there's anything in particular you'd like to work with!