Hardenberg now had a position in that close corporation of sovereigns and statesmen by whom Europe was governed. He accompanied the allied sovereigns to England, and at the Congress of Vienna (1814–1815) was the chief representative of Prussia. But from this time the zenith of his influence, if not of his fame, was passed. In diplomacy he was no match for Metternich, whose influence soon overshadowed his own in the councils of Europe, of Germany, and ultimately even of Prussia itself. At Vienna, in spite of the powerful backing of Alexander of Russia, he failed to secure the annexation of the whole of Saxony to Prussia; at Paris, after Waterloo, he failed to carry through his views as to the further dismemberment of France; he had weakly allowed Metternich to forestall him in making terms with the states of the Confederation of the Rhine, which secured to Austria the preponderance in the German federal diet; on the eve of the conference of Carlsbad (1819) he signed a convention with Metternich, by which — to quote the historian Treitschke — “like a penitent sinner, without any formal quid pro quo, the monarchy of Frederick the Great yielded to a foreign power a voice in her internal affairs.”