Force B was first formed by the Mediterranean Fleet in July 1940. Comprising the battleship and five destroyers, it saw action at the Battle of Calabria under the command of Vice AdmiralAndrew Cunningham. In November 1940 it was involved in Operation MB8, a multi-faceted operation involving several forces with different but co-ordinated aims. During this period Force B comprised the cruisers and and delivered reinforcements to Crete. The force sailed on 4 November with convoy AN 6 en route to Greece, departing that evening to Crete, then heading north to join Force C at Pireaus. From there the combined force under the command of Vice Admiral Henry Pridham-Wippell moved east into the Straits of Otranto to divert the Italian Fleet whilst the balance of the British forces attacked the port of Taranto in Operation Judgement. Whilst in the straits, the cruisers intercepted an Italian convoy of four ships and destroyed three. In March 1941, again under Pridham-Whippel, Ajax and the cruisers Orion, and formed Force B in an operation to bring the Italian fleet to battle, resulting in the Battle of Cape Matapan. In June Force B was re-formed to assist Allied forces in the Syria–Lebanon Campaign with Ajax, Phoebe and four destroyers. During this period ships of the force were engaged by Vichy submarine Caiman, which was damaged in a two-hour hunt, and the destroyers Guepard and Valmy, which left the destroyer Janus badly damaged. In November Force B (comprising Ajax, and two destroyers, and and under the command of Rear AdmiralBernard Rawlings was moved to Malta to reinforce the ships of Force K already there and to carry out offensive sweeps for Axis supply ships en route to Libya. On 19 December, after taking part in conveying a supply ship into Malta in Operation MD 8 which had led to the First Battle of Sirte, Force B was deployed to find the Italian convoy encountered in that engagement but fell foul of a minefield off Tripoli, resulting in the loss of Neptune and Kandahar and damage to two other ships. After this, forces B and K were withdrawn from Malta.
With the outbreak of war in the Pacific and the advance of the Japanese on Malaya and the Dutch East Indies, British naval forces in the Far east were forced to retreat, first to Java, then to Trincomalee, in Ceylon. In March 1942 Admiral James Somerville took command of a force of 29 warships, many approaching obsolescence. To remedy this deficiency he divided his ships into fast and slow divisions, Force A and Force B respectively. This Force B comprised four WWI-vintage Revenge class battleships, the light carrier, the cruisers and and destroyers,, and. These were joined by Dutch cruiser Jacob van Heemskerck and destroyer Isaac Sweers, and RAN destroyers and. This force came under the command of Rear Admiral Algernon Willis. This force came under attack during the Japanese Indian Ocean raid and on 9 April Hermes and Vampire were sunk by aircraft from the |Japanese carrier strike forceKido Butai. After this Force B was withdrawn to Kilindini, in British East Africa, where it was based until the RN could recoup its position in the theatre. Force B's only major action, apart from escort duty was to support Operation Ironclad, the invasion of Vichy-held Madagascar, in May 1942, during which was attacked and damaged by Japanese midget submarines in Diego Suarez harbour.
