Queen Elizabeth 2, often referred to simply as the QE2, is an ocean liner built for Cunard and operated by Cunard as liner and cruise ship from 1969 to 2008. Following her retirement from cruising, she was acquired by Istithmar, the investment company of Dubai World. She was designed as a liner on the transatlantic service from her home port of Southampton, UK, to New York, USA, and was named after the earlier Cunard liner RMS Queen Elizabeth. She served as the flagship of the line from 1969 until succeeded by RMS Queen Mary 2 in 2004. Designed in Cunard's then headquarters and regional offices in Liverpool and Southampton respectively, and built in Clydebank, Scotland, she was considered to be the last of the great transatlantic ocean liners until the construction of the QM2 was announced.

Before she was refitted with a diesel power plant in 1986/87, QE2 was also the last oil-fired passenger steamship to cross the Atlantic in scheduled liner service. During almost forty years of service, the QE2 undertook regular world cruises and latterly operated predominantly as a cruise ship, sailing out of Southampton, England. QE2 had no running mate and never ran a year-round weekly transatlantic express service to New York. QE2 did, however, continue the Cunard tradition of regular scheduled transatlantic crossings every year of her service life.

Elizabeth II (Elizabeth Alexandra Mary; born 21 April 1926) is the constitutional monarch of 16 sovereign states known as the Commonwealth realms, and head of the 54-member Commonwealth of Nations. She is also head of state of the Crown Dependencies.

Elizabeth was born in London, and educated privately at home. Her father acceded to the throne as George VI in 1936 on the abdication of his brother Edward VIII. She began to undertake public duties during the Second World War, in which she served in the Auxiliary Territorial Service. On the death of her father in 1952, she became Head of the Commonwealth and queen regnant of seven independent Commonwealth countries: the United Kingdom, Canada, Australia, New Zealand, South Africa, Pakistan, and Ceylon. Her coronation service in 1953 was the first to be televised. Between 1956 and 1992, the number of her realms varied as territories gained independence and some realms became republics. Today, in addition to the first four aforementioned countries, Elizabeth is Queen of Jamaica, Barbados, the Bahamas, Grenada, Papua New Guinea, the Solomon Islands, Tuvalu, Saint Lucia, Saint Vincent and the Grenadines, Belize, Antigua and Barbuda, and Saint Kitts and Nevis.

RMS Queen Elizabeth was an ocean liner operated by the Cunard Line. With her running mate Queen Mary, she served as a luxury liner between Southampton, UK and New York City, USA via Cherbourg, France. She was also contracted for over twenty years to carry the Royal Mail as the second half of the two ships' weekly express service.

While being constructed, in the mid-1930s by John Brown and Company at Clydebank, Scotland, she was known as Hull 552 but when launched, on 27 September 1938, she was named in honour of Queen Elizabeth, who was then Queen Consort and in 1952 became the Queen Mother. With a design that improved upon that of her running mate, Queen Mary, Queen Elizabeth was a slightly larger ship, the largest passenger liner ever built at that time and for fifty-six years thereafter. She first entered service in February 1940 as a troopship in World War II, and it was not until October 1946 that she served in her intended role as an ocean liner.

With the decline in the popularity of the transatlantic route, both ships were replaced by RMS Queen Elizabeth 2 in 1969. Queen Mary was retired from service in November 1968, and was sold to the city of Long Beach, California. The Queen Elizabeth was sold to a succession of buyers, most of whom had adventurous and unsuccessful plans for her. Finally she was sold to a Hong Kong businessmen Tung Chao Yung who intended to convert her into a floating University cruise ship. In 1972, while undergoing refurbishment in Hong Kong harbour, she caught on fire under mysterious circumstances and was capsized by the water used to fight the fire. In 1973, her wreck was deemed an obstruction, and she was partially scrapped where she lay.