Each man finds himself the space he needs. They shout to one another to spread that way and this way, forwards and back. They loosen the strings on their arrow bags and shake out the shafts. Thomas nocks his own bow. Puts a few shafts in his belt.

He can hardly see the enemy. The wind is not strong, but the sky is full of snow.

Each man stoops to take a piece of the frozen earth in his mouth, just as his grandfather might have done at Agincourt, and to make his sign of the cross on the sod where he’ll stand and possibly die, and for a moment there is silence. Thomas fiddles a nugget of frozen black soil and places it in his mouth. It is tannic and gritty as it melts on his tongue. He holds it aside in his cheek.

Grylle signals and all along the line the captains and the vintenars call out:

‘Nock!’

There is a swathe of movement. Thomas nocks a shaft.

‘Draw!’

‘Loose!’

There. It is done.

The first arrows shoot away with a drumming of strings and grunts of six thousand men. The sky flickers and darkens. He stops and watches, peering through the snow. Will they land on the enemy? There is a distant drum roll. Misty figures twitch in the enemy lines. They are within bowshot.

‘Nock!’ he cries. ‘Draw!’ The fletch of his second shaft tickles his cheek. ‘Loose!’

Walter once said you could tell who was going to win a fight after the first three or four salvoes. Whoever got the most in first would win. They nock, draw and loose three times. More than fifteen thousand arrows.

And in return there is a ripple of something thickening in the snow ahead. The northerners’ arrows land with a sudden spitting patter. They are like bristles in the ground, like a strange crop that no one’ll ever want to eat. They are fifty paces short.

The men laugh. They are delighted.

‘Move up!’ the vintenars bellow. ‘Move up!’

And already the men are charging forward. They stop shy of the ground where the enemy’s arrows are burying themselves with low puffs of soil and ice.

‘Nock! Draw! Loose!’

They repeat the process until they are out of arrows. Thomas’s back is burning. His fingers are skinless and raw. All around him men are grunting with the effort. The rate of firing is fast, ten a minute, but slowing. Men become clumsy as they tire. After two minutes they are done and are left scarlet-faced, heaving for breath, hands on knees, one vomiting with the effort. Sweat stings his eyes and the fog from their bodies blurs his vision.

‘Arrows! Arrows! More shafts! Quickly now!’