Edward Rossiter, and hurried into Cumberland to deal with the English Royalists under Sir Marmaduke Langdale. With his cavalry, Lambert got into touch with the enemy about Carlisle and slowly fell back to Bowes and Barnard Castle. Lambert fought small rearguard actions to annoy the enemy and gain time. Langdale did not follow him into the mountains. Instead, he occupied himself in gathering recruits, supplies of material, and food for the advancing Scots. Lambert, reinforced from the Midlands, reappeared early in June and drove Langdale back to Carlisle with his work half finished. About the same time, the local cavalry of Durham and Northumberland were put into the field for the Parliamentarians by Sir Arthur Hesilrige, governor of Newcastle. On 30 June, under the direct command of Colonel Robert Lilburne, these mounted forces won a considerable success at the River Coquet. This reverse, coupled with the existence of Langdale's Royalist force on the Cumberland side, practically compelled Hamilton to choose the west coast route for his advance. His Scottish Engager army began slowly to move down the long couloir between the mountains and the sea. The Campaign of Preston which followed is one of the most brilliant in English history. Campaign of Preston On 8 July 1648, when the Scottish Engager army crossed the border in support of the English Royalists, the military situation was well defined. For the Parliamentarians, Cromwell besieged Pembroke in West Wales, Fairfax besieged Colchester in Essex, and Colonel Rossiter besieged Pontefract and Scarborough in the north. On 11 July, Pembroke fell and Colchester followed on 28 August. Elsewhere the rebellion, which had been put down by rapidity of action rather than sheer weight of numbers, smouldered, and Charles, the Prince of Wales, with the fleet cruised along the Essex coast. Cromwell and Lambert, however, understood each other perfectly, while the Scottish commanders quarrelled with each other and with Langdale. As the English uprisings were close to collapse, Royalist hopes centred on the Engager Scottish army . It was not the same veteran army of the Earl of Leven, which had long been disbanded. For the most part it consisted of raw levies. The Kirk party had refused to sanction the Engagement (an agreement between Charles I and the Scots Parliament for the Scots to intervene in England on behalf of Charles), causing David Leslie and thousands of experienced officers and men to decline to serve.