This reverse, coupled with the existence of Langdale's force on the Cumberland side, practically compelled Hamilton to choose the west coast route for his advance, and his army began slowly to move down the long couloir between the mountains and the sea. The campaign which followed is one of the most brilliant in English history. When the Scottish army under James Hamilton, 1st Duke of Hamilton invaded England in the summer of 1648, Lambert was obliged to retreat; but Lambert continued to harass the invaders till Cromwell came up from Wales and the Scottish army was destroyed in the three days' fighting at the Battle of Preston fought largely at Walton-le-Dale near Preston in Lancashire. After the battle Lambert's cavalry headed the chase, pursuing the defeated army, and finally surrounded it at Uttoxeter, where Hamilton surrendered to Lambert on 25 August 1648. Lambert then led the advance of Cromwell's army into Scotland, where he was left in charge on Cromwell's return. From December 1648 to March 1649 he was engaged in the successful siege of Pontefract Castle; Lambert was thus absent from London at the time of Pride's Purge and the trial and execution of King Charles I.