After World War II, when Germany was defeated, it was divided into four zones, one for each of the Allies. The eastern part went to the Russians. The other Allied Powers, France, Britain and the U. S. divided the Western portion of the city among themselves. This arrangement reflected the Allied solution for the whole of Germany.
Berlin was an island with special status governed by four nations in the sea of the Soviet Zone of Occupation. In 1947, the Western portion of Germany instituted a government under the watchful eyes of the Western Allies. The Soviet sector followed suit in 1949. During this period, the elaborate governance structure of greater Berlin broke under the strain of Cold War tensions. What emerged was West Berlin, which took up ties with West Germany, known as the Federal Republic of Germany. East Berlin, which comprised the ruins of the old and historic center of Berlin and outlying districts to the East, became the capital of the German Democratic Republic.
After World War II, the Americans pumped capital into West Germany through the Marshall Plan, which resulted in one of the world's strongest economies, enormous prosperity and a stable democracy. Germany has been divided ever since and though at every opportunity, lip service was paid by all western nations to its eventual reunification, no one took the matter seriously. Still bound by very complex regulations, West Berlin began to rebuild in earnest. It was given special treatment by West Germany and by the Allies. Its survival became a symbol of Western commitment against Soviet style communism. Money was pumped in, industries revived, a new University created, since Communist professors and principles dominated the Humboldt University in East Berlin.
But the East German Government, certain that West Berlin would eventually fall to them, was richly inventive in tactics of intimidation. Highways were blocked for hours or days at time, as were canal and rail corridors. Finally, they blockaded the city totally. The Americans - specifically, General Lucius Clay, - invented the Air Lift. For over a year, one B-29 after another flew into Tempel hof Airport and supplied the city until the blockade was lifted. Americans were heroes to West Berliners during in the late 'forties and well beyond.
Berlin cleaned up the war mess, grew and prospered, not quite as dynamically as West Germany, but not too far behind. In June of 1961, Walter Ulbricht, the old head of the German Communist government said in an interview with a Western paper that no one had any intention of building a wall. Widely reported, this caused a massive exodus from the East. They knew then it was coming for sure. Thus, the Wall was constructed by the SED, the Socialist Unity Party of East Germany in August of 1961 as a protective wall against West German fascism and American capitalist imperialism. And for quite some time, it seemed to be working from the perspective of the East German government.
It was really designed to give them breathing room by stopping the flood of refugees. Some East Germans escaped, but they were few. Every sort of invention imaginable was put to the test. People disguised themselves as Russian officers, dug tunnels, and flew home made airplanes, packaged themselves as submarines.
The Berlin Blockade destroyed the lives of many, if not all Berliners. Families were torn apart, and people died trying to move to the better side of the wall. Without the aide of US air lifts, the wall may never have been removed, and lives would be forever changed.