Louis XIV of France the war with a French victory, in order to establish a lasting peace between the Catholic nations. The Queen also gave a partial Catholic orientation to French foreign policy. This was felt by the Netherlands, France's Protestant ally, which negotiated a separate peace with Spain in 1648. In 1648, Anne and Mazarin successfully negotiated the Peace of Westphalia, which ended the Thirty Years' War in Germany. Its terms ensured Dutch independence from Spain, awarded some autonomy to the various German princes of the Holy Roman Empire, and granted Sweden seats on the Imperial Diet and territories to control the mouths
Hessian War Peace Congress mediated by Duke Ernest of Saxe-Gotha and which resulted in a unification and peace treaty that was sealed in April 1648, ahead of the Treaty of Westphalia itself. Before the Westphalian Peace Treaty, Cassel fought one last time against the imperial side, winning the Battle of Wevelinghoven in the Rhineland, together with other Protestant troops. Darmstadt, however, was not involved in this battle. Under the Unification Treaty between Cassel and Darmstadt, Upper Hesse was permanently divided. Darmstadt had to give up a significant part of Upper Hesse to Cassel, not least Marburg and other occupied territories, including the