Lots of stuff about this on the boards over the years and also lots of explanations of the difference.
The thing is though Long Reining, Long Lining and Ground Driving are all exactly the same.
Regrettably there’s folks who don’t seem to know that though.
To be absolutely correct, there’s only Long Reining and Short Reining.
First the terminology, Long Reining: As soon as you put reins from the horse to your hand when you are standing on the ground some distance from the horse then its Long Reining.
Short Reining: is when you are on the ground with short reins to your horse and you stand at the side of your horse at its shoulder and work the reins with one over the horses’s back.
So why is it called lots of different things? I’ll give a full and proper explanation and so folks will truly know and not fall into the trap that others have “of thinking they know”
And trust me this is a subject I do indeed know about.
So here’s a go at further explaining and also with how and why the confusion:
With some in the driving fraternity its called Long Lining or Ground Driving when its done walking behind the horse as if you were carriage driving (but without the vehicle.)
This terminology originates from the farming community or heavy horse folks and its there that this terminology is always still used in Europe. And you may be interested to know that in that community even if they Ground Drive on a circle - then they still call it Ground Driving or Long Lining.
And which one they call it tends to be a regional divide thing: North and South respectively. So go to Somerset and its Long Lining. Go to Yorkshire and its Ground Driving, though the more travelled and refined farmer in Yorkshire would call it Long Lining.
Then that terminology crept into the light harness horse fraternity and purely because as carriage driving expertise declined and trainers have been limited, folks have taken their light harness horses to a guy who has heavy agricultural horses and as far as everyone is concerned he’s “long-lining” or “ground driving”. And because he’s training their horse to carriage drive and he’s doing basic stuff only and probably has about 6 weeks to do it in, the horse is only ever long-reined with the handler walking immediately behind.
Then before you know what has happened folks that know no better think their horse has been “ground driven” or “Long Lined” and it seems can even persuade themselves there’s differences.
But trust me, there’s not!
Said agricultural horse trainer doesn’t need to train this horse to do anything fancy so his ground work will just be to get the horse with a vehicle then away. However if he’s training his own light harness horse - say to drive tandem to go to the hunt - as was the traditional way, then he’d be wanting it VERY well schooled and trained and to a higher level and he’d also do on a circle and teach it to shoulder in and a lot more. But because of his upbringing and culture he’ll still say he’s either Long Lining or Ground Driving.
However the proper terminology is Long Reining and its a form of Advanced Lunging and in many parts of Europe - to confuse things even more, it was called Advanced Lunging in the early days. That though has dropped out of useage because folks who really can Advanced Lunge or Long Rein want to distinguish what they do from those who merely have a horse running round in circles attached one line to a cavesson.
So again the terminology Long Reining is always used by the traditionalists and those who know the correct definitions and don’t have the regional or agricultural culture. So you NEVER hear Prince Philip saying anything other than to Long Rein - whether its in a straight line or in a circle or for riding or driving. My parents and grandparents were the same because even though they were from the north and from a farming community, they were travelled and educated and a little more ‘refined’ and they trained riding horses and top level coaching horses and hackney horses in harness. You would NEVER say to a refined gentleman that his horse had been Ground Driven because even long ago it had associations with basic farm training by an uneducated man.
I hope this explanation helps but if there’s anything I’ve not made clear, then do ask.
Regrettably IMO the history of driving and the old equitation skills and knowledge and language are being lost and I am delighted to share it with others.
Even in the USA though there’s cogniscence of the fact it’s the same thing and carriage drivers frequently disagree which is what.
If you look at this link, you’ll see a book: Introduction to Long Reins “Long reining, long lining or ground driving” a training technique by different names. http://www.wildhorsebooks.com/Light%20Driving.htm