What would living in the past mean for your characters and fictional setting? Whatever world you're in (real or virtual!), there will be good and bad things about this so what are they? What happens to those who seem to be stuck in the past?
What role do historians, archaeologists and archivists play in your fictional world? Who is the custodian(s) of the "official" history (as every government will have one!)?
Have things improved in your fictional world and how? Who was the instigator of needed changes and what resistance did they face? Equally is your fictional world keen to forget/cover up its past and if so why? Does it succeed in doing so?
The past can generate stories too!