About 40 years ago there was a book called The Black Horsemen written by (???) who claimed that a large number of pubs called The Black Horse were sited in what would have been likely battle sites or routes to them when Arthur was fighting the Saxon invaders. He suggested (King) Arthur's men had been mounted on black horses and the pubs are on the sites of earlier inns that commemorated a local tradition. Seems a bit far fetched but I remember the book was quite well written and didn't claim the idea was a new revelation, just a suggested hypothesis.
Anybody else remember it? Has it been debunked?