Vice-Admiral Robert Plampin was a British Royal Navy officer during the late 18th and early 19th centuries, serving in the American Revolutionary War, the French Revolutionary Wars and the Napoleonic Wars, but best known for his time as commander of the British colony of Saint Helena in the South Atlantic during the period when former Emperor Napoleon Bonaparte was imprisoned there. Born into a Navy family, Plampin went to sea at age 13 and fought throughout the American Revolutionary War, based principally in the Caribbean Sea. During the French Revolutionary Wars, Plampin served in a number of ships with mixed success, once being involved in a shipwreck and twice serving ashore during sieges. After the Peace of Amiens, Plampin took command of the ship of the line HMS Powerful and operated successfully in the Atlantic and the Indian Ocean. In 1816, following the defeat and capture of the French Emperor, Plampin was placed in command of the squadron at the Cape of Good Hope, which also had responsibility for Saint Helena, which Plampin regularly visited and had numerous conversations with Napoleon.

HMS Powerful was a 74-gun third rate ship of the line of the Royal Navy. She took part in the defeat of a Dutch fleet in the Battle of Camperdown in 1797, the capture of a French privateer in the action of 9 July 1806, in operations against the Dutch in the East Indies during the raids on Batavia and Griessie in 1806 and 1807, and finally in the Walcheren Campaign during 1809.