World War II
What is it?
World War II was the largest war in history. Fought between the Allied powers (consisting of the United States, Britain and other European nations) and the Axis powers (consisting of Japan, Germany, and the Soviet Union until the Soviet Union was invaded by Germany), it began in 1939 with fighting between European nations but the United States did not enter until the Japanese bombed Pearl Harbor in 1941. After the United States declared war an Japan, Germany also declared war on the United States and the US finally entered into World War II. It ended with an Allied powers victory and decade of unprecedented economic growth and the highest standard to that date.
Why's it important?
World War II lit the spark for the Cold War that would dominate the next 40 years of foreign policy. After World War II, Germany was divided into 4 different sections, each governed by a different country. Those countries were the United States, the United Kingdom, the Soviet Union, and (for whatever reason) France. The Soviet Union wanted more of Germany and eventually took over half of Berlin and it got worse from there, with the threat of nuclear war lasting for decades. On a positive note, the after-effects of World War II included a booming economy and high standard of living. This boost was caused by military spending during World War II and the fact that, since there was nothing to buy, Americans saved a large majority of their money, allowing them to continue to survive even after the soldiers came home and the economy had to adjust to the influx of people and need for jobs.