For more than six decades, Cunard was in strong competition with the White Star Line.
When Cunard launched Lusitania and Mauretania; White Star Line responded by building three large liners - Olympic, Titanic and Britannic.
Olympic was the class leader, and entered service in 1911. She sailed successfully for White Star Line, however by the late 1920's she was ageing.
During the Great Depression, White Star Line merged with Cunard to save off collapse. This was supported by the British Government, which then loaned the newly formed Cunard-White Star enough capital to build Queen Mary and Queen Elizabeth.
Olympic joined the Cunard fold in 1934 and remained in service until 1937. She was then removed from service and scrapped.
Image source: Simplon Post Cards