'Quadrant' was the Allied 1st Quebec Conference, attended by President Franklin D. Roosevelt and Prime Minister Winston Churchill together with their political and military staffs (17/24 August 1943).
The conference was arranged to decide matters of both short- and long-term importance to the two Western Allies, matters which demanded the specific exclusion of the USSR and China.
The primary result of the conference was a joint commitment by the USA and UK to 'Overlord', to be launched on or about 1 May 1944 with the object of securing a lodgement including one or more ports on the southern side of the English Channel so that the Allies could then secure additional area in France for the ground and air exploitation of the initial success with 'operations designed to strike at the heart of Germany and to destroy her military forces'. The basis of the invasion of Europe should be the COSSAC plan, it was decided, and to facilitate the successful implementation of 'Overlord' the conference also decided that General the Hon. Sir Harold Alexander’s Allied 15th Army Group in Italy should exploit its offensive toward Milan and Turin, so pinning as many German divisions as possible, and that the allocation of resources to the Mediterranean should be limited to those required for the success of the Milan/Turin operations, with no thought for the British desire for development into Austria and southern Germany.
It was also decided that an American officer (in fact General Dwight D. Eisenhower) should be appointed to command 'Overlord' though Churchill had previously promised the command to General Sir Alan Brooke, Chief of the Imperial General Staff and the chairman of the Chiefs-of-Staff Committee. For his acquiescence in the matter of Eisenhower, Churchill was permitted to insist on the appointment of Admiral the Lord Louis Mountbatten to the post of Commander-in-Chief, South-East Asia Command.
Churchill also wished to secure Allied approval for 'Culverin ag’ainst northern Sumatra, but this approval was not forthcoming. The real point at issue between the Allies was not so much where their ground forces should be deployed, but the relative allocation of amphibious capability. This was effectively decided by the Americans, who had by far the larger production capacity and need for such craft, and on 6 June 1944 the allocation was 3,696 in the UK for 'Overlord', 3,866 in the Pacific for the twin offensive thrusts of General Douglas MacArthur and Admiral Chester W. Nimitz (both moves jealously preserved by Admiral Ernest J. King, the US Navy commander-in-chief, against the scaling-down efforts of Brooke), and 1,037 in the Mediterranean where, against the wishes of the British, the Americans insisted that the US and rearmed French forces should land between Toulon and Marseille at about the same time as 'Overlord' was implemented. Thus was born 'Anvil', on which the Germans would supposedly be crushed by the hammer of 'Overlord'.
At the 'Quadrant' conference, the Combined Chief-of-Staff planners presented a scheme for the defeat of Japan by means of a US Navy-led push through the central Pacific in concert with a US Army-led advance across South-East Asia to China, so that a naval air blockade of Japan could be instituted as soon as Chinese ports and adjacent airfield areas had been captured. This scheme envisaged the capture of the Philippine islands group, Formosa, Malaya and the Ryukyu islands group in 1945 and 1946 so that final operations against Japan could be started in 1947 for victory in 1948.
The US Joint Chiefs-of Staff were very unhappy about the leisurely pace of this scheme, and demanded an altogether faster progress for Admiral Chester W. Nimitz’s Pacific Ocean Areas and General Douglas MacArthur’s South-West Pacific Area together with the British-led Burma theatre. The Joint Chiefs-of-Staff therefore planned that the Japanese base area of Rabaul on the island of New Britain should be abandoned as a primary target (to be neutralised by air before May 1944 and then left in isolation) as MacArthur’s forces drove to the Vogelkop peninsula at the north-western tip of New Guinea, while Nimitz’s forces took the Marshall, Caroline and Palau island groups before the end of 1944.
With Rabaul now earmarked for neutralisation rather than conquest, a major air campaign was launched from December 1943 by the Air Command Solomons, whose fighters escorted Consolidated B-24 Liberator heavy and North American B-25 Mitchell medium bombers on sorties from airfields on Vella Lavella, New Georgia and Bougainville islands. From January the campaign was joined by land-based dive-bombers, and by the end of that month there was little shipping left to General Hitoshi Imamura’s 8th Area Army and Vice Admiral Chuichi Hara’s 4th Fleet. On 20 February the last Japanese aircraft in the area were withdrawn to Truk, but another three months of attacks were required before the Japanese had been effectively neutralised.
During this time, US thinking switched from concerted drives by MacArthur’s and Nimitz’s forces to twin drives in which Nimitz’s forces would have priority. The reason for this apparent shift in emphasis was the USAAF’s realisation that the central Pacific drive could take the Mariana islands group, whose land area would provide for the construction of air bases from which the new Boeing B-29 Superfortress heavy bomber forces could operate to crush Japanese war-making potential.
In addition to the strategic discussions, which were communicated to Premier Iosif Stalin in the USSR and Generalissimo Chiang Kai-shek in China, the conference also issued a joint statement on Palestine with the object of calming tensions as the British mandated occupation of that territory was becoming increasingly untenable. The conference also condemned German atrocities in Poland.
Churchill and Roosevelt also secretly signed the Quebec Agreement to share nuclear technology in order to build nuclear weapons.