To quote Demitri Martin (taken from this session at around 0:57):
When there's someone who's dead and then someone does something that that person would not have liked, they say that that person is spinning in their grave. But I don't understand why they say that; why is spinning the way that a corpse shows disapproval? [...] If we showed disapproval like that when we were alive, that would make more sense.
Where did this expression spinning in his grave come from? Did it originate in English, or did it come in from another language or culture?