God's Fury, England's Fire_ A New History of the English Civil Wars - Michael J. Braddick [198]
Meanwhile, Waller pursued the royal army, which was moving back via Woodstock and Buckingham. He found it difficult to engage the army, and its very mobility was a problem, since it might suggest a move either on York or on London. Waller therefore had to have the defence of London in mind. This rested on a small and hastily assembled force under Major-General Browne and it appeared vulnerable until Waller made it back to Brentford on 28 June. In the end the indecisive engagement at Cropredy Bridge on 29 June was the only fruit of these manoeuvrings, and this must surely count as a lost opportunity for Parliament. After the battle the royal army was able to march off in pursuit of Essex in better spirits than the parliamentarians.13
In the north, however, the parliamentary campaign was decisive. York had been under siege by Leven and Fairfax since 22 April and the only hope of relief lay with Rupert. In May and June he won a string of victories in Lancashire. These mobile campaigns were frustrating parliamentary armies in the south, but the position in York looked bleak. On 13 June the Earl of Newcastle had been invited to negotiate its surrender and it was thought that the city could only hold out for another six days.14
On 14 June, Charles wrote a fateful letter to Rupert. ‘If York be lost I shall esteem my crown little less, unless supported by your sudden march to me, and a miraculous conquest in the South, before the effects of the Northern power can be found here; but if York be relieved, and you beat the rebels” armies of both kingdoms which were before it, then, but other ways not, I may possibly make a shift upon the defensive to spin out time until you come to assist me’. The loss of York would be a catastrophe except in the very unlikely event that Rupert was able to get away and secure victories in the south before the parliamentarian armies got there. On the other hand, if York was relieved and the northern army defeated, Charles might avoid defeat long enough for Rupert to come to his aid. Relief of York and defeat of the northern army were the best hope for the royalist cause.15
This was a realistic view, but it conflated the relief of York and the defeat of the rebels: as it was to turn out it was possible to relieve York without defeating the Scottish and parliamentarian forces. Charles had not known this of course. His command to Rupert was:
all new enterprises laid aside, you immediately march according to your first intention, with all your force, to the relief of York; but if that be either lost or have freed themselves from the besiegers, or that for want of powder you cannot undertake that work, that you immediately march with your whole strength directly to Worcester, to assist me and my army, without which, or your having relieved York by beating the Scots, all the successes you can afterwards have most infallibly will be useless to me.16
Again, the possibility was not recognized here that York might be relieved without defeating the besieging army.
On 28 June it was clear that Rupert was coming. Besiegers were too exposed between the walls of a defended city and an army able to line up in one place, rather than as an encircling force, and on 1 July the siege had been broken up. The parliamentary