Origins
Postwar division of Germany
When World War II ended in Europe on May 8, 1945, Soviet and Western (U.S., British, and French) troops were located in particular places, essentially, along a line in the center of Europe. From July 17 to August 2, 1945, the victorious Allied Powers reached the Potsdam Agreement on the fate of postwar Europe, calling for the division of a defeated Germany into four occupation zones (thus reaffirming principles laid out earlier by the Yalta Conference), and the similar division of Berlin into four zones, later called East Berlin and West Berlin. The French, U.S., and British sectors of Berlin were deep within the Soviet occupation zones, and thus a focal point of tensions corresponding to the breakdown of the U.S.-Soviet wartime alliance. (See Origins of the Cold War)
The dispute over Berlin
Harry S. Truman refused to give the Soviet Union reparations from West Germany's industrial plants; Joseph Stalin responded by splitting off the Soviet sector of Germany as a Communist state.

The Berlin Airlift

Loading milk on a West Berlin-bound planeOn June 23, 1948, the three Western sectors ended the use of occupation currency and introduced the deutsche mark. The Soviets objected to this move, and this appears to have been their justification for the Berlin Blockade.

On June 24, 1948, the Soviet Union blocked access to the arteries of the three Western-held sectors of Berlin, which was deep within the Soviet zone of Germany, by cutting off all rail and road routes going through Soviet-controlled territory in Germany. The Western powers had never negotiated a pact with the Soviets guaranteeing these rights. Amid the fallout of the London Conference, the Soviets now rejected arguments that occupation rights in Berlin and the use of the routes during the previous three years had given the West legal claim to unimpeded use of the highways and railroads.

General Lucius D. Clay suggested sending a large armoured column driving peacefully, as of right, down the Autobahn from West Germany to West Berlin, but prepared to defend itself if it were stopped or attacked. But President Harry S. Truman, following the consensus in Washington, believed this entailed an unacceptable risk of war, in which the U.S. might be unpopular. So Clay was told to take advice from General Curtis LeMay commander USAF Europe to see if an airlift was possible. By chance General Albert Wedemeyer, the Army Chief of Plans and Operations, was in Europe on an inspection tour when the crisis occurred. He had been commander of the U.S. China Theater (USFCT) in 1944–1945 and had an intimate knowledge of the World War II Allied airlift from India over the Hump of the Himalayas into China both to supply the Nationalist Chinese Army and the U.S. Twentieth Air Force engaged on Operation Matterhorn. He was in favour of the airlift option and knew who was the best man to run the operation: Lieutenant-General William H. Tunner was tasked with organising and commanding the Berlin airlift because of his experience of commanding and organising the airlift over the Hump.

On June 25 Clay gave the order to launch a massive airlift (ultimately lasting 324 days) that flew supplies into the Western-held sectors of Berlin over the blockade during 1948-1949. The first airplane flew on the following day, and the first British airplane flew on the 28th. This aerial supplying of West Berlin became known as the Berlin Airlift. Military confrontation loomed while Truman embarked on a highly visible move which would publicly humiliate the Soviets.

The U.S. action was given the name Operation Vittles. An existing British supply plan known as Knicker which evolved into 'Carter Paterson', and then from early July become Operation Plainfare.

Hundreds of aircraft, nicknamed Rosinenbomber ("raisin bombers") by the local population, were used to fly in a wide variety of cargo items, including more than 1.5 million tons of coal. At the height of the operation, on April 16, 1949, an allied aircraft landed in Berlin every minute, and 12,840 tons of freight were delivered. The actual containers ranged from large containers to small packets of candy with tiny individual parachutes intended for the children of Berlin. The aircraft were supplied and flown by the United States, United Kingdom and France, but crews also came from Australia, Canada, South Africa and New Zealand to help. Ultimately 278,228 flights were made and 2,326,406 tons of food and supplies were delivered to Berlin.

On April 4, 1949, the Western powers signed the North Atlantic Treaty founding NATO, declaring that an attack on any one would be considered an attack against them all.

The USSR lifted its blockade at 23:59, on May 11, 1949. However, the airlift did not end until September 30, as the Western nations wanted to build up sufficient amounts of supplies in West Berlin in case the Soviets blockaded it again.

The major Berlin airfields involved were Tempelhof, in the American Sector, Gatow and the Havel lake in the British and Tegel (built by army engineers in 49 days with the help of Berlin volunteers) in the French. Operational control of the three allied airlift corridors was given to BARTCC (Berlin Air Route Traffic Control Center) air traffic control located at Tempelhof. Diplomatic approval authority was granted to a secretive four-power organization also located in the American sector. It was called the Berlin Air Safety Center (BASC). The creation of the BASC also lead to increased tensions between the US and Soviet Union.

The Allied commander during the airlift was General Lucius D. Clay. He would return to Berlin during the second Berlin crisis, leading up to the building of the Berlin Wall and the Checkpoint Charlie crisis.

British operation
Initially the British had about 150 C-47 Dakotas and 40 Avro Yorks. By the 18th July , the RAF was running 995 tons per day into Berlin. In July the Dakotas and Yorks were joined by 10 Short Sunderland and 2 Short Hythe flying boats flying from the Elbe near Hamburg to the Havel See. The flying boats speciality was transporting bulk salt which would have been corrosive to the other planes. In November Handley Page Hastings were added to the fleet and some crews and aircraft were removed to train others. By mid December the RAF had landed 100,000 tons of supplies. In April 1949, civilian companies involved in the airlift were formed into a Civil Airlift Division (British European Airways) to operate under RAF control. In mid-April the combined airlift of all nations operations managed in 24 hours to make 1,398 flights, carrying 12,940 tons (13,160 t) of goods, coal and machinery, beating their record of 8,246 (8,385 t) set only days earlier.