What sparked the beginning of World War II in Europe?

The beginning of World War II in Europe is widely recognized as being sparked by Germany's invasion of Poland in 1939. This invasion took place on September 1, 1939, when Nazi Germany, led by Adolf Hitler, launched a blitzkrieg approach to warfare, which emphasized speed and surprise to overwhelm the Polish defenses.

The invasion of Poland was a direct violation of international treaties and marked a significant escalation in aggressive expansion by the German regime, which sought to overturn the post-World War I order established by the Treaty of Versailles. Following this act of aggression, Britain and France declared war on Germany on September 3, 1939, officially marking the beginning of World War II in Europe.

While the other options relate to significant events in the context of World War II, they do not directly correspond to the initiation of the conflict in Europe. The bombing of Pearl Harbor, for instance, occurred later in 1941 and was pivotal for the United States' entry into the war, but it did not trigger the war in Europe itself. The invasion of France happened in 1940, during the course of the war, and the rise of fascism in Italy set the stage for conflict but was not the immediate cause of the war's