#TIL that the DADGAD guitar tuning I've been trying out for a few days, though commonly known as traditional "Celtic" was, in fact, brought back from Morocco by Davy Graham in the 1960s, based on an oud tuning he heard there. He adapted to guitar then it was copied by many in the British Islands folk revival.
We invent so much of our 'shared cultural history' while simply stealing whatever we like from other cultures and hating what we don't like. "What did the Romans ever do for us?" :-)