As I have suggested elsewhere, history is to the nation as memory is to the individual. As a person deprived of memory becomes disoriented and lost, not knowing where he has been or where he is going, so a nation denied a conception of its past will be disabled in dealing with its present and its future.The above is by Aurthur Schlesinger Jr. in the current print issue of The New York Review of Books, History and National Stupidity. (Sorry no link, the online version requires an additional paid subscription which I don't have.) It is a good introduction to Bilmon's latest, Munich, which I suggest you go read.
But conceptions of the past are far from stable. They are perennially revised by the urgencies of the present. When new urgencies arise in our own times and lives, the historian's spotlight shifts, probing now into the shadows, throwing into sharp relief things that were always there but that earlier historians had carelessly excised from the collective memory. New voices ring out of the historical darkness and demand attention.