In June 1940, just before the fall of France, Mussolini brought Italy into the war on Hitler's side. The Italian dictator was not really ready for war, but Hitler's easy successes were beginning to alarm him. He thought that if he did not join his German ally soon, than Italy would not get its share of the spoils.

The entry of Italy into the war posed serious problems for Britain. It meant that her trade route through the Mediterranean was cut. In addition, with colonies in Libya, Eritrea, Somaliland and Abyssinia, the Italians were in a position to threaten British interests in Africa and the Middle East. These interests included Egypt and the Suez Canal, the British bases of Malta, Cyprus and Aden, and areas which were under British control at that time such as Palestine, the Sudan and East Africa.

In fact, Italy did not prove to be as dangerous as the British feared. Although Mussolini wanted war, few of the ordinary Italian people had any enthusiasm for it. As a result, when the fighting actually started, Italy did not do at all well. The Italian invasion of Greece met with humiliating setbacks and small British forces cleared the Italians out of Abyssinia and Eritrea. In addition Italy's navy suffered heavy losses. The British Fleet Air Arm destroyed part of her fleet in Taranto in November 1940, and in March of the following year several Italian cruisers were sunk in an engagement with the Royal Navy off Cape Matapan.

Even in North Africa, where they had made a special effort to launch an attack on the Suez Canal, the Italians were defeated. First of all the Italian troops under Graziani were cleared out of Egypt. Then the British, in a brilliant campaign led by General Wavell, swept into Libya. Almost everywhere it was necessary for the Germans to step in to save their Italian allies from total defeat.