HMS Cumberland was a 70-gun third rate ship of the line of the Royal Navy, launched on 21 October 1842 at Chatham Dockyard. She carried a crew of 620 men. Cumberland recommissioned as a flagship under Captain George Henry Seymour as the flagship of his father, Vice-Admiral Sir George Francis Seymour. She served on the North America and West Indies Station. In March 1854 she sailed to the Baltic Sea as the Crimean War with Russia was imminent. Cumberland was involved in the Battle of Bomarsund, an Anglo-French attack on Bomarsund in the Grand Duchy of Finland in August 1854. On 15 March 1858, Cumberland ran aground on an uncharted rock in the River Plate off the Isla de Flores, Uruguay. Her captain and master were both acquitted at the subsequent court martial held on board HMS Impregnable