World War II
World War II was the central event of the twentieth century. It involved all six major continents, all three of the great oceans on the planet, scores of countries, and billions of people. It caused 57 million deaths and unimaginable human suffering. It brought about the redrawing of national boundaries in Europe and Asia, forced the relocation of many ethnic groups, made millions of families homeless, and led to the virtual annihilation of the Jewish population of Europe. By the time it was over in 1945, Tokyo, Berlin, Hamburg, Leningrad, Stalingrad, Warsaw, Hiroshima, Dresden, Dusseldorf, Nagasaki, Osaka, Manila, Cologne, and dozens of other great cities had been obliterated. And population centers that had mostly avoided the worst of the death and destruction continued to see poverty and hunger linger for years after the surrender documents had been signed. Meanwhile, the prisoners and the wounded, making their way back to wives, sweethearts, parents, and children, often after an absence of many years, would carry the cost of the conflict with them for the rest of their lives.