Marston Moor, a large open plain of Yorkshire, England, 8 in. N. W. of York, where a decisive victory was gained by the parliamentary forces and the Scots, under Lord Fairfax and the earl of Leven, over the royalists commanded by Prince Rupert, July 2, 1644. The advance of the royalists toward York, which was invested by Fairfax, having compelled the latter to raise the siege, he retired to Marston Moor, where Rupert encountered him on the afternoon of July 2 with 25,000 men. The parliamentary army was of about equal strength. The battle commenced with an ineffectual cannonade on both sides, after which a pause of two hours ensued, each army watching the other across a brook. At 7 o'clock in the evening the signal for close combat was given, and Rupert, who commanded the right wing of the royalists, falling impetuously upon the parliamentary left wing, routed it, and pursued the fugitives several miles. The parliamentary centre was in like manner driven back by the royalist infantry with great loss, and the fortune of the day seemed so desperate that the three parliamentary generals, Lord Fairfax and the earls of Manchester and Leven, fled in different directions. But the imprudence of Rupert ruined his cause.
That part of the parliamentary left consisting of Cromwell's brigade of ironsides and David Leslie's Scottish regiments, with some fugitives rallied by Sir Thomas Fairfax, taking advantage of the disordered condition of the cavaliers, who were scattered in pursuit orepgaged in plundering the baggage of their enemies, charged them in a compact body with such vigor that after a few brief shocks the royal army was driven from the field, ami its artillery, consisting of 25 pieces, with more than 100 colors and 1,500 prisoners, captured. The royalist loss in killed and wounded exceeded 2,000, and that of the parliamentary army was nearly as great. A few days afterward York surrendered to Fairfax, 'and the power of the parliament was permanently established in the north of England.