HMS Britannia was a 120-gun first-rate ship-of-the-line of the Royal Navy, laid down in 1813 and launched on 20 October 1820. Commissioned in 1823, she saw service in the Mediterranean from 1830-1 and in 1841. She was decommissioned in 1843, before returning to service for the Crimean War, serving as flagship of Admiral Sir James Deans Dundas, commanding the British fleet in the Mediterranean and Black Sea from 1851–4.. She was engaged in the Bombardment of Sebastopol on 17 October 1854 during the Crimean War. On 14 November 1854, she was driven ashore on the Russian coast and was reported to have 5 feet (1.5 m) of water in her hold.