Under the Treaty of the Pyrenees, signed on November 5, 1659, France gained Artois and Hainaut along its border with the Spanish Netherlands, as well as Roussillon, or Northern Catalonia. These were more significant than often assumed; in combination with the 1648 Treaty of Münster, France strengthened its borders in the east and south-west, while in 1662, Charles II sold Dunkirk to France. Acquisition of Roussillon established the Franco-Spanish border along the Pyrenees, but divided the historic Principality of Catalonia, an event still commemorated each year by French Catalan-speakers in Perpignan. In addition to these territorial loses, Spain was forced to recognize and confirm all of the French territorial gains at the Peace of Westphalia.