Thirty Years' War on the inhabitants of occupied territories. The war also bankrupted most of the combatant powers. The Dutch Republic enjoyed contrasting fortune; it was removed from the Holy Roman Empire and was able to end its revolt against Spain in 1648 and subsequently enjoyed a time of great prosperity and development, known as the Dutch Golden Age, during which it became one of the world's foremost economic, colonial, and naval powers. The Thirty Years' War ended with the Treaty of Osnabrück and the Treaties of Münster, part of the wider Peace of Westphalia. The war altered the previous political order of
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