RMS Lusitania was an ocean liner launched by the Cunard Line in 1906. She was the world's largest passenger ship until the completion of the Mauretania three months later and was awarded the Blue Riband appellation for the fastest Atlantic crossing in 1908. The Lusitania was sunk on her 202nd trans-Atlantic crossing, on 7 May 1915 by a German U-boat 11 miles (18 km) off the Old Head of Kinsale, Ireland, killing 1,197 passengers, crew and stowaways. The sinking occurred about two years before the United States declaration of war on Germany but significantly increased public support in the US for entering the war.

RMS Mauretania was a British ocean liner designed by Leonard Peskett and built by Wigham Richardson and Swan Hunter on the River Tyne, England for the Cunard Line, launched on the afternoon of 20 September 1906. She was the world's largest ship until the launch of RMS Olympic in 1910. Mauretania captured the eastbound Blue Riband on the maiden return voyage in December 1907, then claimed the westbound Blue Riband for the fastest transatlantic crossing during her 1909 season. She held both speed records for 20 years.