He joined the
Diplomatic Service and in 1803 was appointed ambassador to the
Hanse Towns, minister-resident of Great Britain at
Hamburg (at that time a "free city"), and
chargé d'affaires to the
Circle of Lower Saxony. On the night of 24 October 1804 Rumbold was abducted by French troops on the pretext that British Ministers on the Continent had conspired against France.
Joseph Fouché, the Minister of Police in Paris, had sent an order in the name of
Napoleon to
Marshal Bernadotte commanding French occupation troops in
Hanover. A detachment of 250 French troops embarked in boats at
Harburg, in Hanoverian territory. They crossed the river
Elbe, landed on the Hamburg side, proceeded to Rumbold's residence, forced the door, and compelled him to deliver up his papers. He was then taken to Hanover in a guarded coach, thence to Paris, and confined in the
Temple. In
Berlin great indignation was expressed and the
King of Prussia, as Protector of the Circle of Lower Saxony and guardian of the free cities, ordered his minister at Paris to demand Rumbold's release. The next day, on the orders of
Napoleon, he was conveyed to
Cherbourg and put on board a French cutter, sailing under flag of truce, which delivered him to the British frigate
Niobe, in which he arrived at
Portsmouth. The papers seized at Hamburg remain in the
Archives nationales in Paris and reveal no conspiracy. Rumbold returned to Hamburg where he was replaced in 1806. He died of fever at
Memel on 15 December 1807. ==Family==