Jérôme Bonaparte thus received more attention since the famous "Treaty of Westphalia" which ended the Thirty Years' War a hundred and fifty years earlier in 1648. Thanks to these efforts by King Jerome, Kassel celebrated an enormous cultural upturn. However, Jérôme's expensive habits earned him the contempt of Napoleon. His court incurred expenses comparable to Napoleon's court (which oversaw a vastly larger and more important realm), and Napoleon refused to support Jérôme financially. In 1812, Jérôme was given command of a corps in the "Grande Armée", marching towards Minsk. Insisting on travelling "in state", Napoleon reprimanded Jerome, ordering him to leave his
Peace of Münster for approval; it was ratified by the Spanish and Dutch delegations on 15 May, with the States General narrowly approving the Treaty on 5 June 1648. The Peace of Münster together with the Treaty of Münster between the Holy Roman Emperor, France and their allies and the Treaty of Osnabrück involving the Holy Roman Empire, Sweden and their allies were collectively known as the Peace of Westphalia. While European conflict continued, this marks a significant point in the transition to sovereignty based on states rather than individuals e.g. the Hapsburgs. Sovereignty has been defined by historian Harry Hinsley as "the