so the letter mentions William Wallace, of Scotland so why should it be returned to Scotland? Still don't understand.
Of course it might be nice if it was in Scotland but why " should it be returned"?
Perahps I;m being very slow here, but on that basis all sorts of things should be returned just because someone had either a mention or temporary possession of an object. If the letter was from a French King to an Italian Agent mentioning a Scottish man, I can't see that it should automatically go to a museum in Scotland.