RMS Mauretania was an ocean liner designed by Leonard Peskett and built by Swan, Hunter & Wigham Richardson for the British Cunard Line, and launched on the afternoon of 20 September 1906. She was the world's largest ship until the completion of RMS Olympic in 1911 as well as the fastest until Bremen's maiden voyage in 1929. Mauretania became a favourite among her passengers. After capturing the Eastbound Blue Riband on her maiden return voyage in December 1907, she claimed the Westbound Blue Riband for the fastest transatlantic crossing during her 1909 season. Mauretania would hold both speed records for twenty years.

The ship's name was taken from Mauretania, an ancient Roman province on the northwest African coast, not the modern Mauritania which is now to the south. Similar nomenclature was also employed by Mauretania's running mate, Lusitania, which was named after the Roman province directly north of Mauretania, across the Strait of Gibraltar, the region that now is Portugal. Mauretania remained in service until 1934 when Cunard White Star retired the ship and then scrapping commenced in 1935.