In 1644 King and Parliament were so closely matched that any accession of strength to either party would tend to the speedy conclusion of the conflict. When, on the 4th of March, the Earl of Leven occupied Sunderland with 30,000 Scots, reinforcements for Parliament, the greatest concern was felt by all good Cavaliers, and the Marquis of Newcastle promptly brought up his Yorkshire Royalists, and held Leven at bay.

In this strait Sir Thomas Fairfax was ordered to the North to reinforce the Scots with cavalry, and enable them to engage the King’s men. Lord Fairfax joined his son near Hull, and, augmenting his forces, it was resolved to attack Selby, which was defended by barricades, and garrisoned by a strong force of foot and horse under the command of Colonel Bellasis, the son of Lord Falconberg.

On the 11th of April, 1644, the Parliamentarians advanced to the storm. The army was formed into three divisions, commanded by Lord Fairfax, Sir John Meldrum, and Colonel Bright. Sir Thomas Fairfax supported with his cavalry.

The steady advance was met by the red flash of the guns, and the smoke rose and drifted over the front. But the drums beat on, the pikemen held bravely to the front, and the musketeers began to handle their guns, as the front ranks poured into the trenches, leaving on the green sward behind them the silent forms of slain men, whose white, drawn faces looked very sad in the midst of the fresh young grass, and under the shifting April clouds. In the trenches and by the barricades some hot work went on, with clash of pikes and hail of bullets, until the Cavaliers were fairly beaten from their defences, and their reluctant officers, failing to rally their disordered ranks, retired them from the front. The lines were won, but Colonel Bellasis held the open ground with his horse, ready to sweep back the hostile foot should they attempt any further advance, and a desultory fire of musketry was maintained, until Sir Thomas Fairfax succeeded, after a fierce struggle, in breaking down a barricade and making way for his horse. Then the files of heavy cavalry came crashing over the disputed ground, beating under hoof the heaps of debris and rubbish, and overthrowing all who strove with pike and musket to bar their path. Sir Thomas occupied the ground between the houses and the river, when, with trumpets sounding the charge, a numerous body of royal horse bore down upon them. The charge was gallantly received, and a severe conflict ensued, when, beaten back by dint of steel and lead, the Royalists broke away in confusion, and availing themselves of the bridge of boats, crossed the river and took to flight.

Scarcely had the panting warriors time to re-form their disordered ranks before the fiery Bellasis burst upon them in a furious charge, eager to avenge his defeated horse. Cold steel met in thrust and parry; the pistols flashed, and brave men fell thickly as, hand-to-hand, in dust and smoke, the sharp hot melee held; then riderless steeds broke away from the shock; Sir Thomas was hurled from his steed amid plunging hoofs and slashing steel, but was rescued by his gallant troopers, and re-mounted. The Cavaliers fought as King’s men should that day, but were over-weighted by Fairfax’s heavy horse, and driven off in headlong flight for York, leaving Colonel Bellasis a prisoner in the hands of the victorious Roundheads.

In the meantime the Parliamentarian foot had made good their hold of the town, and accepted the surrender of the royal foot.

The results of this engagement were remarkable. The Fairfaxes had only defeated some two or three thousand men, and wrested a small town from the King’s hands, yet the strong city of York trembled for its safety, and Newcastle was urgently requested to return and defend the county. He complied. The Scots were at liberty. Fairfax immediately joined them with his little army; and, on the 19th of April, York was blockaded by the combined forces. Manchester augmented the besieging army; York was closely invested, its fall was imminent; and King Charles urgently demanded of Prince Rupert the raising of the siege. Gallantly was the demand met, but was followed by the famous battle of Marston Moor, from the effects of which the royal cause never recovered.