So what is the mystery? Well, I looked up Blooody Furlong on the company website (http://www.celticmarches.com/shop/bloody-furlong/) and read the following:
"Charles 1st led his Cavaliers through Bromyard in 1645 on his way to fight Cromwell's Roundheads. A ferocious battle was fought on 'Bloody Furlong' which is now one of our apple orchards."
Try as I might, I could find no information about its engagement on the internet! I assume it was in the run up to Naseby but this is just a guess!
If anyone out there has any more information, I'd be very interested to hear about it!