On May 5, 1646, a beleaguered Charles I of England surrendered to Scottish forces under Alexander Leslie, Lord Leven. Charles was between a rock and a hard place - Parliamentary forces or Scots Covenanters. Walter Scott covers this history in his "Tales of a Grandfather":
"...In circumstances so desperate, it was difficult to make a choice. A frank surrender to the Parliament, or an escape abroad, would have perhaps been the most advisable conduct. But the Parliament and their own independent army were now on the brink of quarrelling. The establishment of the Presbyterian Church was resolved upon, though only for a time and in a limited form, and both parties were alike dissatisfied ; the zealous Presbyterians, because it gave the Church courts too little power ; the Independents, because it invested them with any control whatever over persons of a different communion. Amidst the disputes of his opponents, the King hoped to find his way back to the throne.
For this purpose, and to place himself in a situation, as he hoped, from whence to negotiate with safely, Charles determined to surrender himself to that Scotish army which had been sent into England, under the Earl of Leven, as auxiliaries of the English Parliament. The King concluded that he might expect personal protection, if not assistance, from an army composed of his own countrymen. Besides, the Scottish army had lately been on indifferent terms with the English. The Independent troops, who now equalled or even excelled them i:i discipline, and were actuated by an enthusiasm which the Scots did not possess, looked with an evil eye on an army composed of foreigners and Presbyterians. The English in general, as soon as their assistance was no longer necessary, began to regard their Scottish brethren as an incumbrance ; and the Parliament, while they supplied the Independent forces liberally with money and provisions, neglected the Scots in both these essentials, whose honour and interest were affected in proportion. A perfect acquaintance with the discontent of the Scottish army, induced Charles to throw himself upon their protection in his misfortunes.
He left Oxford in disguise, on 27th April, having only two attendants. Nine days after his departure, he surprised the old Earl of Leven and the Scottish camp, who were then forming the siege of Newark, by delivering himself into their hands. The Scots received the unfortunate monarch with great outward respect, but guarded his person with vigilance. They immediately broke up the siege, and marched with great speed to the north, carrying the person of the King along with them, and observing the strictest discipline on their retreat. When their army arrived at Newcastle, a strong town which they themselves had taken, and where they had a garrison, they halted to await the progress of negotiations at this singular crisis.
Upon surrendering himself to the Scottish army, King Charles had despatched a message to the Parliament, expressing his having done so, desiring that they would send him such articles of pacification as they should agree upon, and offering to surrender Oxford, Newark, and whatever other garrisons or strong places he might still possess, and order the troops he had on foot to lay down their arms. The places were surrendered accordingly, honourable terms being allowed ; and the army of Montrose in the Highlands, and such other forces as the Royalists still maintained throughout England, were disbanded, as I have already told you, by the King's command.
The Parliament showed great moderation, and the civil war seemed to be ended. The articlesof pacification which they offered were not more rigorous than the desperate condition of the King must have taught him to expect. But questions of religion interfered to prevent the conclusion of the treaty.
In proportion as the great majority of the Parliament were attached to the Presbyterian forms, Charles was devoted to the system of Episcopacy. He deemed himself bound by his coronation oath to support the Church of England, and he would not purchase his own restoration to the throne by consenting to its being set aside. Here, therefore, the negotiation betwixt the King and his Parliament was broken off; but another was opened between the English Parliament and the Scottish army, concerning the disposal of the King's person.
If Charles could have brought his mind to consent to the acceptance of the Solemn League and Covenant, it is probable that he would have gained all Scotland to his side. This, however, would have been granting to the Scots what he had refused to the Parliament"; for the support of Presbytery was the essential object of the Scottish invasion. On the 'other hand, it could hardly be expected that the Scottish Convention of Estates should resign the very point on which they had begun and continued the war. The Church of Scotland sent forth a solemn warning, that all engagement with the King was unlawful. The question, therefore, was, what should be done with the person of Charles..."