The "Dorsetshire" was part of a scratch fleet of obsolete British battleships with two small obsolete aircraft carriers and attached cruisers hurriedly put together to stem the Japanese naval advance into the Indian Ocean. Admiral James Somerville had moved the main part of the fleet to a secret base at Addu Atoll in the Maldives, as he knew that his fleet was no match for the Japanese. His main duty was to keep the sea lanes open to India, to the Persian Gulf oilfields and to the Eighth Army in Egypt, at that time attempting to stop the German and Italian armies under General Erwin Rommel.