In the summer of 1638 Charles had found that his high words for using force against the Covenanters could not be matched by the means at his disposal. Within England and, more peripherally, Wales and Ireland, the administrative effort of organising armies and shipping was both expensive and slow. From within the particular troublespot of Scotland Charles's advisers urged upon him patience and caution, but as he remained fixed in his purpose his attention to counsel was selective. After the Glasgow Assembly the chosen path of the new year was a military drive of grand proportions. For all three kingdoms it was to be a powerful assertion of royal authority; whether or not the Covenanters dared to answer by use of arms, Charles was committed to overwhelming their challenge. Their rebellion could not be tolerated.

Because of the seriousness of the Scottish troubles, Charles himself was to go north. A commitment to the rights of royal majesty was to be vindicated in person; he would proceed at least to York, the northern capital of England. The Marquis of Hamilton continued as the King's Commissioner, but with a less inclusive brief of rallying the loyal forces in Scotland and commanding a naval assault up the east coast. His direct contact with Charles became more a matter of strategic communications. However, because the element of winning Scottish support remained, he kept contact both with Covenanter leaders and anti-Covenanters in the hope of forging a middle way.