[["World war one started in 1914. The first hostilities of the second world war began with the invasion of China by Japan in 1937. The war officially began in Europe when Germany invaded Poland in 1939.", 339.0], ["On September 1, 1939, Hitler invaded Poland. Two days later the United States and England declared war on Germany. That was the start of World War II.", 49.0], ["World War I was fought during the early 1900's. In the teens. I can't recall the exact years. Check on the internet. World War II started in 1939 and ended, officially, on June 6, 1945. But the USA entered the war on December 7, 1941.", 0.0]]
when did world war one world war two start
history