Sir Ralph Hopton, the best of the royalist generals, took the command of their army as it advanced into Somerset, and drew the stress of the war into the West. Essex despatched a picked force under Sir William Waller to check their advance; but Somerset was already lost ere he reached Bath, and the Cornishmen stormed his strong position on Lansdowne Hill in the teeth of his guns. But the stubborn fight robbed the victors of their leaders; Hopton was wounded, and Greenvil slain; while soon after, at the siege of Bristol, fell two other heroes of the little army, Sir Nicholas Slanning and Sir John Trevanion, " both young, neither of them above eight and twenty, of entire friendship to one another, and to Sir Bevil Greenvil." Waller, beaten as he was, hung on their weakened force as it moved for aid upon Oxford, and succeeded in cooping up the foot in Devizes. But the horse broke through, and joining a force which Charles had sent to their relief, turned back, and dashed Waller's army to pieces in a fresh victory on Roundway Down. The Cornish rising seemed to decide the fortune of the war; and the succours which his Queen was bringing him from the army of the North determined Charles to make a fresh advance upon London. He was preparing for this advance, when Rupert in a daring raid from Oxford on the Parliamentary army, met a party of horse with Hampden at its head, on Chalgrove field.

The skirmish ended in the success of the royalists, and Hampden was seen riding off the field before the action was done, " which he never used to do," with his head bending down, and resting his hands upon the neck of his horse. He was mortally wounded, and his death seemed an omen of the ruin of the cause he loved. Disaster followed disaster. Essex, more and more anxious for a peace, fell back on Uxbridge; while a cowardly surrender of Bristol to Prince Rupert gave Charles the second city of the kingdom, and the mastery of the West The news fell on the Parliament "like a sentence of death."' The Lords debated nothing but proposals of peace. London itself was divided; "a great multitude of the wives of substantial citizens" clamoured at the door of the Commons for peace; and a flight of six of the few peers who remained at Westminster to the camp at Oxford proved the general despair of the Parliament's success.

From this moment, however, the firmness of the Parliamentary leaders began slowly to reverse the fortunes of the war. If Hampden was gone, Pym remained. The spirit of the Commons was worthy of their great leader: and Waller was received on his return from Round-way Hill "as if he had brought the King prisoner with him." A new army was placed under the command of Lord Manchester to check the progress of Newcastle in the North. But in the West the danger was greatest. Prince Maurice continued his brother Rupert's career of success, and his conquest of Barnstaple and Exeter secured Devon for the King. Gloucester alone interrupted the communications between his forces in Bristol and in the north; and Charles moved against the city, with hope of a speedy surrender. But the gallant resistance of the town called Essex to its relief. It was reduced to a single barrel of powder when the Earl's approach forced Charles to raise the siege; and the Puritan army fell steadily back again on London, after an indecisive engagement near Newbury, in which Lord Falkland fell, "ingeminating 'Peace, peace!'" and the London trainbands flung Rupert's horsemen roughly off their front of pikes.

In this posture of his affairs nothing but a great victory could have saved the King, for the day which witnessed the triumphant return of Essex witnessed the solemn taking of the Covenant. Pym had resolved at last to fling the Scotch sword into the wavering balance; and in the darkest hour of the Parliament's cause Sir Harry Vane had been despatched to Edinburgh to arrange the terms on which the aid of Scotland would be given. First amongst them stood the demand of a " unity in Religion;" an adoption, in other words, of the Presbyterian system by the Church of England. Events had moved so rapidly since the earlier debates on Church government in the Commons that some arrangement of this kind had become a necessity. The bishops to a man, and the bulk of the clergy whose bent was purely episcopal, had joined the royal cause, and were being expelled from their livings as "delinquents." Some new system of Church government was imperatively called for by the religious necessities of the country; and, though Pym and the leading statesmen were still in opinion moderate Episcopalians, the growing force of Presbyterianism, and still more the needs of the war, forced them to seek such a system in the adoption of the Scotch discipline.

Scotland, for its part, saw that the triumph of the Parliament was necessary for its own security; and whatever difficulties stood in the way of Vane's wary and rapid negotiations were removed by the policy of the King. While the Parliament looked for aid to the north, Charles had been seeking assistance from the Irish rebels. The massacre had left them the objects of a vengeful hate such as England had hardly known before, but with Charles they were simply counters in his game of king-craft. The conclusion of a truce with the Confederate Catholics left the army under Lord Ormond, which had hitherto held their revolt in check, at the King's disposal for service in England. With the promise of Catholic support Charles might even think himself strong enough to strike a blow at the Government in Edinburgh; and negotiations were soon opened with the Irish Catholics to support by their landing in Argyleshire a rising of the Highlanders under Montrose. None of the King's schemes proved so fatal to his cause as these. As the rumour of his intentions spread, officer after officer in his own army flung down their commissions, the peers who had fled to Oxford fled back again to London, and the royalist reaction in the Parliament itself came utterly to an end.