It is known that he had a share in the drawing up of the new constitutions for the Batavian and Italian Republics.
The stadholderate, the offices of captain and admiral-general, and all the ancient organization of the United Netherlands were abolished, and were transformed into the Batavian Republic, in close alliance with France.
His action in the matters just named, as also in the complex affair of the secularizations of clerical domains in Germany (February 1803), belongs properly to the history of those countries; but we may here note that, even before the signature of the peace of Amiens (27th of March 1802), he had effected changes in the constitution of the Batavian (Dutch) republic, which placed power in the hands of the French party and enabled him to keep French troops in the chief Dutch fortresses, despite the recently signed treaty of Luneville which guaranteed the independence of that republic. His treatment of the Italians was equally high-handed.
Under King Louis Napoleon he was secretary-general for foreign affairs, but resigned office on the annexation of the Batavian republic to France.
True, she now agreed to recognise the independence of the Cisalpine, Ligurian, Helvetic and Batavian (Dutch) republics; but the masterful acquisitiveness of the First Consul and the weak conduct of Austrian and British affairs at that time soon made that clause of the treaty a dead letter.
This system had already been applied to the Batavian republic in 1795, totheLigurian and Cisalpine republics in June 1797; it was extended to that of MUlhausen on the 28th of January 1798, to the Roman republic in February, to the Helvetian in April, while the Parthenopaean republic (Naples) was to be established in 1799.
France recognized the integrity of the Turkish Empire and promised an indemnity to the House of Orange exiled from the Batavian (Dutch) Republic since 1794.
In February 1803, as a result of the peace of Amiens, the colony was handed over to the Batavian Republic, which introduced many needful reforms, as had the British during their eight years' rule.
It was now made the capital of the Batavian Republic and afterwards of the kingdom of Holland.
In 1799 Bonaparte, through whose influence his release had been obtained, sent him to the Hague to consolidate the alliance between France and the Batavian Republic. In this mission he was entirely successful, and he is credited with another diplomatic success in the inception of the Austrian marriage.