The price of war gradually began to outweigh the potential gains. This was true for Spain and for the Republic. Moreover, the Dutch were eager to obtain official recognition of their national sovereignty. Negotiations took two years to complete. The Dutch Republic was recognised as a free country.
When the Twelve Year Truce ended in 1621, war resumed where it had ended. Both sides concentrated on capturing strategically located cities and forts. After Stadholder Maurice died in 1625, he was succeeded by his half-brother Frederick Henry. He was given responsibility as captain general to implement the new strategy of creating a buffer beyond the defensive line of the IJssel, Maas and Scheldt rivers. Frederick Henry became known as the taker of cities or ‘stedendwinger’: he captured Groenlo, Den Bosch and Venlo, Roermond and Maastricht. In 1635, the Dutch joined France in launching an attack on the Spanish armies in the Southern Netherlands. With the capture of Breda, Sas van Gent and Hulst, the Republic was surrounded by a string of buffer towns.
In addition to the losses in the Netherlands, in 1640 the Spanish king Phillip IV also faced problems closer to home. Rebellions against Spanish rule had erupted in Catalonia and Portugal. Meanwhile, war was also taking its toll in the Republic. The enormous cost of the conflict had created a huge national debt, while some of Holland’s influential patricians were beginning to question the need for continued hostilities: after all, the frontier was secure now that Breda was recaptured. Commercial cities like Amsterdam were especially keen on ending the war, although other towns still remained belligerent: these were towns that were making a good profit from the conflict.
Despite many misgivings, the Dutch Republic decided to enter talks about a truce. These took place in the town of Munster, a German bishopric. On 30 January 1648, Spanish and Dutch representatives signed the peace treaty. For the Republic this represented more than just an end to the Eighty Years War, it meant a definitive recognition of national sovereignty. When news of the peace broke, exuberant celebrations were held around the country.