One thing the Battle of Towton was not was Lancashire v Yorkshire. I am sure that most of you are well aware of this, but I find that many people are under the delusion that the Wars of the Roses were a Lancashire v Yorkshire fixture. Cricket may have caused this confusion. Or maybe stupidity.
Anyway, passing lightly on. The commanding general on the Lancastrian side was Henry Beaufort, Duke of Somerset, a young man of 25 and a veteran of both the battles of St. Albans and of Wakefield. (He had commanded at 2nd St.Albans and Wakefield, so had a winning track record.) King Henry VI, Queen Margaret and Prince Edward were all safely left behind in York, a prudent and sensible precaution.
We can safely assume that Somerset commanded the Lancastrian centre. Their right was under Henry Percy, Earl of Northumberland. His flank was usefully protected by the Cock Beck. It is less clear who commanded the left but a fair guess is Henry Holland, Duke of Exeter, by virtue of his rank. (He had few other qualities, but his rank was undeniable.)
On the Yorkist side, Edward IV commanded the centre in person. Their right was under Lord Fauconberg whose performance the previous day was soon to be equalled on this one. Warwick is the most likely commander of their left, facing Percy.
Snow began to fall, and as the morning drew on it turned into something of a blizzard. Fortunately for the Yorkists, the wind was blowing from the south, into the very faces of their opponents. Fauconberg advanced his men, who shot arrows into the Lancastrian left wing. The Lancastrians naturally tried to reply in kind, but because of their conditions their arrows fell short, while the Yorkist ones were 'wind assisted.' The Yorkists eventually ran out of arrows to shoot, but by stepping forward a little way were able to replenish their stocks with the Lancastrian arrows that had fallen short.
The Lancastrians now advanced so as to fight at close quarters. Although doubtless badly mauled by the arrow storm, there were still plenty of them left and anxious to give a good account of themselves. The lines locked together, and an almost unimaginable slugfest ensued, men hacking at one another in the snow.
The blizzard eased somewhat, but it seems likely that visibility was limited and that most of those engaged were only aware of their own local situation. From time to time men drew off to rest; possibly they did so by silent, mutual agreement. However the conflict was always renewed, and it went on for hours, through daylight and beyond. The strength and courage of all concerned must have been tested to the limit. Slowly, faced with superior numbers, the Yorkists were forced back.
Suddenly, out of the gloom, the Duke of Norfolk's division arrived to reinforce the Yorkists. Norfolk, who had been seriously left behind the advance of the main Yorkist force, evidently marched in haste to the 'sound of the guns' or the general racket of a major battle. His men peppered the Lancastrian left with arrows and then fell upon its flank. After what it had already endured that day it's not surprising that the Lancastrian left faltered and broke before this new onslaught.
It was not long before the rest of the Lancastrian army followed suit, as soaring Yorkist morale pushed their men forward in one last effort. Before long the battle had turned into a pursuit and slaughter, halted only by the gathering darkness of night. Many Lancastrians drowned trying to ford the Cock while others were trapped in a killing ground next to it and slaughtered. Edward had ordered that there should be no quarter. The days of 'kill the lords and spare the commons' were over.