The parleyings at Muenster made slow headway, as so many thorny questions had to be settled.

Meanwhile, with the full approval of the prince, negotiations were being secretly carried on between Madrid and the Hague with the view of arriving at a separate understanding, in spite of the explicit terms of the treaty of 1635.

As soon as the French became aware of what was going on, they naturally protested and did their utmost to raise every difficulty to prevent a treaty being concluded behind their backs.

The old questions which had proved such serious obstacles in the negotiations of 1607-9 were still sufficiently formidable.

But the situation was very different in 1646-7.