Both Hesse-Cassel and Brunswick were supportive of Prussia and hostile to France and Napoleon was undoubtedly in no mood to haggle after Prussia declared war on him in September 1806. He was organizing the Confederation of the Rhine in the summer of 1806 which completely alienated Prussia and Austria, though Austria was not ready to contest it. Napoleon 'interfered' in what was Prussia's strategic goal-becoming the most powerful German state and absorbing the smaller German states, a goal that was partially achieved at the Congress of Vienna. The Prussian war of liberation was for the purpose of 'liberating' as much of Germany as possible and absorbing that territory into Prussia.