In vain did the Cardinal Infante with a powerful force try to break through the lines of circumvallation, which the prince had constructed with his usual skill.
Called away by a French invasion on the south, he had to leave Breda to its fate.

The town surrendered on October 10.
During the years 1637 and 1638 the ever-recurring dissensions between the province of Holland and the Generality became acute once more.

The Provincial Estates insisted on their sovereign rights and refused to acknowledge the authority of the States-General to impose taxes upon them.

This opposition of Holland was a great hindrance to the prince in the conduct of the war, and caused him constant anxiety and worry.

It was impossible to plan or to carry out a campaign without adequate provision being made for the payment and maintenance of the military and naval forces, and this depended upon Holland's contribution.