HMS Barham was a World War I vintage battleship, launched on Clydebank on 31 December 1914. She served as a flagship with the Grand Fleet and took part in the Battle of Jutland. She was refitted between the wars, and anti-torpedo blisters were added.
During World War II, she was part of Admiral Cunningham’s eastern Mediterranean battle-squadron, which included her sister ships HMS Queen Elizabeth and HMS Valiant.
The U-331 penetrated the battle-squadron’s destroyer screen and fired three torpedoes at the Barham. All of them struck home. The ship’s magazine exploded and the Barham sank with great loss of life: over 800 sailors killed.
Once again, the wisdom of Hitler’s decision to send additional U-boats to the Mediterranean was confirmed. The loss of the Barham was a severe blow to British sea power in the Mediterranean, coming so soon after the loss of the Ark Royal.