Hessian War died out, and peaked after 1645 in the Hessian War proper. This open warfare began with the Siege of Marburg in 1645 and ended in April 1648 (but before the Treaty of Westphalia which was concluded later that year and ended the Thirty Years' War) with victory going to Hesse-Cassel. In the aftermath, Upper Hesse was divided and parts of its territory went to the now stronger Hesse-Cassel. At a European level the Hessian War must be viewed in the larger context of the Thirty Years' War, in which the reformed Hesse-Cassel sided with the Protestant Swedish party, whilst Hesse-Darmstadt,
Treaty of the Pyrenees princess entered France. In addition, the English received Dunkirk, although they elected to sell it to France in 1662. The Treaty of the Pyrenees was the last major diplomatic achievement by Cardinal Mazarin. Combined with the Peace of Westphalia, it allowed Louis XIV remarkable stability and diplomatic advantage by means of a weakened Louis II de Bourbon, Prince de Condé and a weakened Spanish Crown, along with the agreed dowry, which was an important element in the French king's strategy: All in all, by 1660, when the Swedish occupation of Poland was over, most of the European continent was at