Mauretania sailed on her maiden voyage from Liverpool to New York on 17 June 1939 under the command of Captain
Arthur Tillotson Brown (who had delivered the previous
Mauretania to the shipbreakers), after remaining in New York for a week she returned to Southampton via Cherbourg on Friday, 30 June 1939. Like , 25 years before,
Mauretania was to experience only the briefest period of commercial operation before the outbreak of hostilities halted this work for over six years. Returning from the next voyage,
Mauretania called at Southampton, , with 2,036
German prisoners of war on board, 16 September 1942 On 11 August 1939 she left on her final prewar voyage to New York. She began her return voyage on September 30, and on October 2 the German English-language radio broadcast from Hamburg issued a veiled threat against her. On her return she was requisitioned by the government.
Mauretania was armed with two guns and some smaller weapons, painted in battle grey, and then despatched to America at the end of December 1939. For three months the ship lay idle in New York, docked alongside , , and the
French Line's , Other notable liners in this great convoy were , , , and . During the early stages of the war the ship transported Australian troops to Suez, India and Singapore but later she mainly served in the North Atlantic. In addition she shuttled Italian prisoners of war from the Middle East to South Africa, for internment, after their defeat in North Africa. Like
Aquitania, she amassed over during the course of her war duties, first crossing of the Indian Ocean, then working the Atlantic with American and Canadian troops and finally serving in the Pacific. One of her wartime voyages, of , took her right around the world, taking 82 days to complete. During this epic voyage she established a speed record for the crossing time from
Fremantle, Australia to
Durban, South Africa. The distance was covered in 8 days and 19 hours at an average speed of . Another wartime troop transport voyage began in New York on 10 May 1943 and ended in
Bombay on 24 June 1943, with calls en-route at
Trinidad, Rio de Janeiro,
Cape Town and
Diego-Suarez. On 8 January 1944 she was involved in a minor collision with the American
tanker Hat Creek in New York harbour. During World War II, she travelled and carried over 340,000 troops.
Mauretania was not designed to be an exceptionally fast ship and during six years of war duty, her engines had received little attention but still achieved a turn of speed in 1945 making the passage from Bombay to the UK via the Cape at an average speed of . After the war's end,
Mauretania made several further voyages for the government repatriating troops.
Mauretania took the first dedicated sailing of British
war brides and their children being patriated to Canada to join their husbands, landing at
Pier 21 at
Halifax, Nova Scotia in February 1946. On 2 October 1946 she returned to Liverpool, was released from government service and immediately went into
Gladstone Dock to be reconditioned by
Cammell Laird & Co. for return to Cunard-White Star service. == Post-war (1947–1962) ==