Eighty Years' War other areas, although the heartland of the republic was no longer threatened; this included the beginnings of the Dutch Colonial Empire, which at the time were conceived as carrying overseas the war with Spain. After a 12-year truce in which the Dutch Republic achieved de facto recognition, hostilities broke out again around 1619, which can be said to coincide with the Thirty Years' War. An end was reached in 1648 with the Peace of Münster (a treaty part of the Peace of Westphalia), when the Dutch Republic was definitively recognised as an independent country no longer part of the Holy
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