In the Mediterranean. Italy entered the war on June 10, 1940, with an army of 1,500,000, a modern navy, and a highly rated air force. The first naval action in the Mediterranean came on July 20. It resulted in the sinking of the Italian cruiser Bartolomeo Colleone by the Australian cruiser Sydney. Italy attacked Greece on October 28, and the British, in an effort to secure the eastern Mediterranean, sent troops to the Greek island of Crete. The British struck at the Italian fleet at Taranto on November 11-12. In this action, planes from the carrier Illustrious damaged three battleships and a cruiser, crippling the Italian fleet.
In 1939, a group of scientists, many having recently arrived in the United States after fleeing Nazi persecution in Germany, informed government officials that recent experiments conducted in Germany had demonstrated the feasibility of building an atomic weapon.
This World War II timeline highlights important dates from April 1940 to December 1940. On May 10, 1940, Hitler had his troops begin the invasion of France in lands the Allies thought impassible by an army. Follow the events of World War II and the German invasion.