As if to confirm the instructions, the heralds break off and ride back to their own ranks and almost at once there is a storm of arrows from the Lancaster side, shooting downhill and finding targets. A sigh, a defeated sigh, comes from the York side and we can see the men going down on their knees in a swift prayer, before rising to their feet and pulling on their helmets.

‘What are they doing?’ asks avidly.

‘They are kissing the ground,’ I say. There is something terrible about the doomed men putting their lips to the earth that they think will be their deathbed. ‘They are kissing the ground where they will be buried. They know they will be defeated and yet they are not running away.’

‘Too late to run,’ the queen says harshly. ‘We would chase them and kill them.’

From our vantage point we can see that the Yorks are outnumbered by almost two to one, perhaps even more. This is not going to be a battle, it is going to be a massacre.

‘Where is Lord Stanley?’ the queen demands. ‘He wanted to lead the attack but I ordered him to be in support. Where is he?’

I look around. ‘Could he be hiding in ambush?’

‘Look!’ she says.

The very centre of the York army, where they should be at their strongest, is giving way before the arrows. ‘They’re retreating!’ the queen cries. ‘We’re winning! So quickly!’

They are. The men at the very centre of the line are turning, dropping their weapons, and running away. At once I see our cavalry come forwards and start the charge downhill, towards the stream. I clasp my hands together as I see Elizabeth’s husband, out in front, thundering into the shallow water and riding across, struggling up the steep banks of the far side, just as the York forces inexplicably swing round and run back into the very heart of the battle, picking up their weapons and returning to the fight.

‘What’s happening?’ Margaret is as bewildered as I am. ‘What are they doing?’

‘They’ve come back,’ I say. ‘They’ve turned. It was a trick, and now our cavalry is bogged down in the river and the Yorks are able to fight them from the bank. They have tricked us off our good position, into the river, and our men can’t get out.’

It is a terrible sight. Our men in battle armour on their metal-plated horses go plunging into the water, and then struggle to get up the other side of the stream where they are battered by the York men at arms, wielding great swords, war axes and pikes. The knights fall from their horses, but cannot get to their feet to defend themselves, the horses’ hooves crash down through the water to crush them as they struggle to rise, or weighed down by their flooded breastplates they drown, scrambling in the churning waters of the stream. Those who can grab a stirrup leather try to pull themselves up but the Yorks are dancing up and down the dry banks, quick to thrust a knife in an unguarded armpit or lean towards the stream to slash at a throat, or one of the strong soldiers steps into the stream, swinging a great battle axe, and down goes the Lancaster knight into the water, which blooms red. It is a savage muddle of men and horses. There is nothing beautiful about it, or noble, or even orderly, nothing like the battles that are made into ballads or celebrated in the romances. It is a savage mess of brutish men killing each other for blood lust. A few of the Lancaster lords scramble up the bank on their great war horses and tear through the York lines and disappear – they simply run away. Worse, even more of them, hundreds of them, drop their swords point down to indicate they are not fighting, pull up their horses into a walk, and go slowly, humbly, towards the enemy lines.