Steamship RMS Queen Mary is launched.

RMS Queen Mary is a retired British ocean liner that sailed primarily on the North Atlantic Ocean from 1936 to 1967 for the Cunard-White Star Line and was built by John Brown & Company in Clydebank, Scotland. Queen Mary, along with RMS Queen Elizabeth, were built as part of Cunard's planned two-ship weekly express service between Southampton, Cherbourg and New York. The two ships were a British response to the express superliners built by German, Italian and French companies in the late 1920s and early 1930s.

Queen Mary sailed on her maiden voyage on 27 May 1936 and won the Blue Riband that August; she lost the title to SS Normandie in 1937 and recaptured it in 1938, holding it until 1952, when it was taken by the new SS United States. With the outbreak of World War II, she was converted into a troopship and ferried Allied soldiers during the conflict.

Following the war, Queen Mary was refitted for passenger service and along with Queen Elizabeth commenced the two-ship transatlantic passenger service for which the two ships were initially built. The two ships dominated the transatlantic passenger transportation market until the dawn of the jet age in the late 1950s. By the mid-1960s, Queen Mary was ageing and was operating at a loss.

After several years of decreased profits for Cunard Line, Queen Mary was officially retired from service in 1967. She left Southampton for the last time on 31 October 1967 and sailed to the port of Long Beach, California, United States, where she was permanently moored. The City of Long Beach bought the ship to serve as a tourist attraction featuring restaurants, a museum and a hotel. The city contracted out management of the ship to various third-party firms over the years. It took back operational control in 2021 when the operator filed for bankruptcy and it was found that extensive repairs were needed to keep the ship from sinking.

A steamship, often referred to as a steamer, is a type of steam-powered vessel, typically ocean-faring and seaworthy, that is propelled by one or more steam engines that typically move (turn) propellers or paddlewheels. The first steamships came into practical usage during the early 1800s; however, there were exceptions that came before. Steamships usually use the prefix designations of "PS" for paddle steamer or "SS" for screw steamer (using a propeller or screw). As paddle steamers became less common, "SS" is assumed by many to stand for "steamship". Ships powered by internal combustion engines use a prefix such as "MV" for motor vessel, so it is not correct to use "SS" for most modern vessels.

As steamships were less dependent on wind patterns, new trade routes opened up. The steamship has been described as a "major driver of the first wave of trade globalization (1870–1913)" and contributor to "an increase in international trade that was unprecedented in human history".