On the same day he wrote to Legge:

"I have had no answer to ten letters I wrote, but from the Duke of Richmond, to whom I wrote plainly and bid him be plain with the King, and to desire him to consider some way which might lead to a treaty, rather than undo his posterity. How this pleases I know not, but rather than not do my duty and speak my mind freely, I will take his unjust displeasure."[[3]]

This advice was in fact exceedingly displeasing to the King. Richmond, who fully concurred in Rupert's opinion, showed the letter to his master "with as much care and friendship to Rupert" as possible; and the King read it graciously, saying that his nephew had "expressed as great generosity as was all his actions;"[[4]] but, for all that, he firmly forbade him to write in such a strain again. "Speaking as a mere soldier or statesman," he acknowledged that Rupert might be right; but, "as a Christian, I must tell you that God will not suffer rebels and traitors to prosper, nor this cause to be overthrown; and whatever personal punishment it shall please Him to inflict on me must not make me repine, much less give over this quarrel; and there is little question that a composition with them at this time is nothing less than a submission, which, by the grace of God, I am resolved against, whatever it cost me. For I know my obligation to be, both in conscience and honour, neither to abandon God's cause, injure my successors, nor forsake my friends. Indeed I cannot flatter myself with expectation of good success more than this, to end my days with honour and a good conscience; which obliges me to continue my endeavours, as not despairing that God may yet, in good time, avenge his own cause.... I earnestly desire you not in any way to hearken after treaties, assuring you, low as I am, I will not go less than what was offered in my name at Uxbridge. Therefore, for God's sake, let us not flatter ourselves with these conceits; and believe me, the very imagination that you are desirous of a treaty will lose me so much the sooner."[[5]]

But noble and earnest as were the King's words, they could not alter his nephew's mind. Rupert had little faith that a miracle would be vouchsafed to save the royal cause; and he could never be made to understand that the questions at issue were such as admitted of no compromise. Digby of course seized the opportunity of widening the breach between King and Prince. Ever since Marston Moor, he had intrigued with increasing success against his rival, and Rupert struggled vainly in his meshes. "I would give anything to be but one day in Oxford, when I could discover some that were in that plot of Herefordshire and the rest. But I despair of it!"[[6]] the Prince had written in the March of this year. In June he had sent Langdale to Ormonde in Ireland, as a counterfoil to O'Neil, and Digby hastened to let the Lord Lieutenant know that Langdale was "a creature of Prince Rupert, and sent over not without jealousy that Dan O'Neil may be too frank a relater of our military conduct here."[[7]] And, July 21st, 1645, it is entered in the Prince's diary: "Ashburnham told the Prince that Digby would ruin him."[[8]] By that time Rupert had become convinced that Digby would succeed in his endeavours. A week later he wrote passionately to Legge, from Bristol: "You do well to wonder why Rupert is not with the King! When you know the Lord Digby's intention to ruin him you will not then find it strange."[[9]]

Digby's chance was close at hand. Throughout July and August Rupert busied himself at Bristol, circling about the country, pacifying and winning over the Clubmen and trying to supply the deficiencies of the Bristol stores. This town was now the most important garrison of the King. It was the key of the Severn. It alone held Wales and the Marches loyal, and its loss would also terribly affect the Royalists in the south-west. Rupert had assured the King that he could hold the place four months, and great was the horror and dismay when he surrendered it after a three weeks' siege.

The truth was that he had found the town insufficiently supplied, greatly undermanned, and full of despondency and disaffection. He had done his best to remedy these evils; he ordered the townspeople to victual themselves for six months, imported corn and cattle from Wales, and he started manufactories of match and bullets within the town. All the recruits he could gain were "new-levied Welsh and unexperienced men," and even of these there were but few. "After the enemy approached, His Highness never could draw upon the line above 1,500," and this to defend a stretch of five miles![[10]] Moreover, all his Colonels assured him that the wall was not tenable against a vigorous assault. The one chance was that, if they repulsed the first storm, the enemy might be discouraged, and the approaching winter might save the city for yet a little while.

On September 4th Fairfax sat down before Bristol, and summoned Rupert to surrender, in rather peculiar language. The summons was a private exhortation to the Prince himself, and a personal appeal to his sense and humanity, "which," says Fairfax, "I confess is a way not common, and which I should not have used but in respect to such a person, and such a place."[[11]] He proceeded to explain that the Parliament wished no ill to the King, but only his return to its care and Council, and entreated Rupert to end the schism by a surrender without bloodshed. The Prince only replied by demanding leave to send to ask the King's pleasure. This Fairfax refused to grant, and Rupert entered into a treaty, hoping thereby to spin out time until relief could come. But the patience of Fairfax was soon exhausted. On September 10th he assaulted the city, about 2.0 a.m., entered the lines at a spot held by some new recruits, and was, by daybreak, in full possession of line and fort. Thus the enemy was already within the city, and Rupert had no hope of relief, for, since Naseby, the King had had no army in the field. Moreover, since the siege began, no word had come to the Prince from any quarter. Three courses now lay open to him. He might, with his cavalry, break through Fairfax's army, leaving behind him just sufficient men to keep the castle; this plan was rejected as exceedingly dangerous and unsatisfactory. Secondly, he might retreat to the castle, which could be held for a long time; but the castle would not contain all the cavalry, and thus a large portion of it, together with the "nobility, gentry and well affected of the town," would be left to the mercy of the conquering foe.[[12]] Thirdly and lastly, he could surrender on honourable terms; and this was the course chosen by the Council of War. Rightly or wrongly, Rupert entered into treaty, and a cessation of arms was agreed on. But the cessation was violated by Fairfax's men, and Rupert thereupon declared that he "would stand upon his own defence, and rather die than suffer such injuries."[[13]] Fairfax hastened to apologise and make amends; Rupert was pacified, and the treaty concluded. The terms were good and honourable; the garrison were to march out with the honours of war, a charge of bullet and powder was granted to each of the Prince's guards, the sick were to stay uninjured in the city, and no private person was to be molested. It must also be noted that Rupert yielded only at the second summons, and after the city had been entered by the enemy. Relief was "as improbable to be expected as easy to be desired," and though he could certainly have held the castle longer, "the city had been thereby exposed to the spoil and fury of the enemy, and so many gallant men who had so long and faithfully served His Majesty, (whose safeties His Highness conceived himself in honour obliged to preserve as dearly as his own) had been left to the slaughter and rage of a prevailing enemy."[[14]] It may be that Rupert mistook his position. Perhaps he should have held the castle entrusted to him at all costs, and suffered no other considerations to cross his military councils. But his unwillingness to desert the townspeople and his beloved cavalry, can hardly be counted to his discredit.

On September 10th the Royalist garrison marched out of Bristol, and was escorted by Fairfax himself for two miles over the Downs. Rupert had dressed himself carefully for his part, and there was nothing of the broken down Cavalier about his attire. "The Prince was clad in scarlet, very richly laid in silver lace, and mounted upon a very gallant black Barbary horse; the General (Thomas Fairfax) and the Prince rode together, the General giving the Prince the right hand all the way."[[15]] The courtesy on both sides was perfect; the Puritans showed no unseemly triumph over their fallen foe, and the Prince bore himself towards his conquerors as a soldier and a gentleman should. "All fair respects between the Prince and Sir Thomas Fairfax," reported a Puritan witness; "much respect from the Lord General Cromwell. He (the Prince) gave this gallant compliment to Major Harrison, 'that he never received such satisfaction in such unhappiness, and that, if ever in his power, he will repay it,'"[[16]]

Truly Rupert shone more in evil fortune than in good, and he seems to have completely won the hearts of his enemies. His request for muskets for his men was readily granted, on his promise to deliver them up to the Parliamentary convoy, at the end of his journey, "which every one believes he will perform,"[[17]] said an adherent of the Parliament. And the Puritan Colonel Butler, who convoyed him from Bristol to Oxford, wrote of him to Waller, with enthusiasm. "I had the honour to wait upon His Highness Prince Rupert, with a convoy from Bristol to this place, and seriously, I am glad I had the happiness to see him. I am confident we have been much mistaken in our intelligence concerning him. I find him a man much inclined to a happy peace, and he will certainly employ his interest with His Majesty for the accomplishing of it. I make it my request to you that you use some means that no pamphlet is printed that may derogate from his worth for the delivery of Bristow. On my word he could not have held it, unless it had been better manned."[[18]] Changed indeed was the Puritan attitude towards the mad Prince, and more than one officer of the Parliament was eager to justify his conduct. "I have heard the Prince much condemned for the loss of that city, but certainly they were much to blame," wrote another. "First let them consider that the town was entered by plain force, with the loss of much blood. And then the Prince had nothing to keep but the great fort and castle. Perchance he might hold out for some weeks, but then, of necessity, he must have lost all his horse, which was in all, 800; and he had no expectation of any relief at all. Let all this be considered, and no man can blame him."[[19]]

But the advocacy of the Parliament was not likely to allay Royalist indignation; nay, it was but another proof of Rupert's collusion with the enemy! The Queen spoke "largely" of her nephew, giving out in Paris that he had sold Bristol for money;[[20]] and the story gained colour from the fact that the Elector really did receive a large sum from the Parliament at this time. The loss of Shrewsbury was brought up against Maurice, and it was rumoured that the younger Princes were in league with the Elector; though they had never once written to him, since he had chosen to identify himself with the Parliament. Here was Digby's opportunity; and the King, overwhelmed by the unexpected catastrophe, listened to his representations. On his arrival at Oxford, Rupert received, from the hands of Secretary Nicholas, his discharge from the army, a passport to leave the country, and a letter from the King, desiring him "to seek subsistence somewhere beyond seas."[[21]] Further, Nicholas was directed to deprive Legge of the Governorship of Oxford, and to place him under arrest.