He spent a great deal of money in building the "New Castle" in Stuttgart and elsewhere, and sided against Prussia during the Seven Years' War of 1756–1763, which was unpopular with his Protestant subjects. His whole reign featured dissension between ruler and ruled, the duke's irregular and arbitrary methods of raising money arousing great discontent. The intervention of the emperor and even of foreign powers ensued and, in 1770, a formal arrangement removed some of the grievances of the people. Charles Eugene did not keep his promises, but later, in his old age, he made a few further concessions. Charles Eugene left no legitimate heirs, and was succeeded by his brother, Louis Eugene (died 1795), who was childless, and then by another brother, Frederick Eugene (died 1797). This latter prince, who had served in the army of Frederick the Great, to whom he was related by marriage, and then managed his family's estates around Montbéliard, educated his children in the Protestant faith as francophones. All of the subsequent Württemberg royal family were descended from him. Thus, when his son Frederick II became duke in 1797, Protestantism returned to the ducal household, and the royal house adhered to this faith thereafter. Nevertheless, the district legislatures as well as the imperial diets offered a possibility of regulating matters in dispute. Much was left over from the trials before the imperial courts, which often lasted decades. In the wars after the French Revolution in 1789, Napoleon, the emperor of the French, rose to be the ruler of the European continent. An enduring result of his policy was a new order of the southwestern German political world. When the French Revolution threatened to be exported throughout Europe in 1792, Baden joined forces against France. Its countryside was devastated in the ensuing battles. In 1796, the margrave was compelled to pay an indemnity and to cede his territories on the left bank of the Rhine to France. Fortune, however, soon returned to his side. In 1803, largely owing to the good offices of Alexander I, emperor of Russia, the margrave received the Bishopric of Konstanz, part of the Rhenish Palatinate, and other smaller districts, together with the dignity of a prince-elector. Changing sides in 1805, he fought for Napoleon, with the result that, by the peace of Pressburg in that year, he obtained the Breisgau and other territories at the expense of the Habsburgs (see Further Austria).