The military action known as 'Operation Compass' was the first large British military operation of the Western Desert Campaign (1940–1943) during the Second World War. British, Indian, Commonwealth and Allied forces attacked Italian forces of the 10th Army (Marshal Rodolfo Graziani) in western Egypt and Cyrenaica, the eastern province of Libya, from December 1940 to February 1941.

Great Britain controlled the Suez Canal and Italy, as part of the Axis along with Germany and Japan, sought to wrest control of it for their own purposes, so they mounted an attack on British forces in Egypt.

The Western Desert Force (WDF) (Lieutenant-General Richard O'Connor) with about 36,000 men, advanced from Mersa Matruh in Egypt on a five-day raid against the Italian positions of the 10th Army, which had about 150,000 men in fortified posts around Sidi Barrani in Egypt and in Cyrenaica. The WDF swiftly defeated the Italians in their fortified posts and at Sidi Barrani and the British exploited their success, forcing the rest of the 10th Army out of Egypt and capturing the ports along the Libyan coast.

The British took over 138,000 Italian and Libyan prisoners, hundreds of tanks, and more than 1,000 guns and many aircraft, against WDF losses of 1,900 men killed and wounded, which was about 10 per cent of the infantry.

Italian reinforcements were rushed to Libya to defend Tripoli, assisted by the 'Deutsches Afrikakorps' and Luftwaffe, and a long, drawn-out desert campaign followed.

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