Strength of the Armies
While Rupert was in favor of retreating, Charles listened to Lord Digby, his secretary of state, who claimed that a retreat would further damage morale. Hindsight is 20/20 of course, but in reality, the Royalist army was in no shape to take on the highly-trained New Model Army. Charles’ army consisted of just 7,400 men with 4,100 horsemen and 3,300-foot soldiers. The New Model Army held a significant advantage with 14,000 men including 6,000 cavalry 7,000 infantry, 1,000 dragoons, and 11 guns.
One of the keys to the battle was the fact that Fairfax had the sense to realize that the New Model Army had yet to reach its potential. He waited five days for Cromwell to arrive with reinforcements so by June 13, his army was ready. In contrast, Charles was also waiting for support, but it was too far away to help. He was expecting Royalist support from Wales and Somerset, and while the Welsh arrived too late, the Somerset regiment didn’t arrive at all. Charles made a mistake by attacking Leicester and abandoning the trip north. The ease of the victory at Leicester probably caused him to overestimate his strength.
Tactics
The Battle of Naseby took place on June 14, but fog prevented the two armies from spotting one another in the morning. Before hostilities had begun, the New Model Army was ready for battle at the top of a ridge overlooking Naseby. The problem was, it was too good a position. Cromwell wanted the Royalists to attack and leave themselves open. If the New Model Army remained in its excellent position, even the incompetent Charles would think twice about launching an attack.
As a result, Cromwell ordered the army to move to a location 1.5 miles from Naseby. On the morning of the battle, the armies were no more than 800 meters apart. Cromwell positioned himself on the right flank with around 3,500 cavalry, and he was directly opposed by Sir Marmaduke Langdale on the Royalist side. Henry Ireton was on the left flank of the New Model Army and would face up against Prince Rupert and his brother, Prince Maurice. King Charles remained in command of a small reserve force.
Ultimately, the Parliamentary forces had soldiers and equipment that they didn’t even need. While it had 11 pieces of artillery, it proved useless in the heat of battle. The first salvo was fired too high and soon after the battle began, the two armies were so close that the artillery couldn’t be used. By the time battle commenced, the New Model Army completely outflanked the Royalist left. With superior forces and better commanders, the outcome of the Battle of Naseby was never in doubt.