Italian invasion of Egypt

Main article: Italian invasion of Egypt

Battle Area of Operation Compass December 1940 to February 1941

Italy declared war on the United Kingdom on 11 June 1940.^[4] Bordering on the Italian colony of Libya was the Kingdom of Egypt. Although a neutral country, Egypt was occupied by the British under the terms of the Anglo-Egyptian Treaty of 1936, which allowed British military forces to occupy Egypt if the Suez Canal was threatened.^[5] A series of cross-border raids and skirmishes began on the frontier between Libya and Egypt. On 13 September 1940, an Italian force advanced across the frontier into Egypt, reaching Sidi Barrani on 16 September,^[6] where the advance was halted until logistical difficulties could be overcome.^[7]
Italy's position in the centre of the Mediterranean Sea made it unacceptably hazardous to send ships from Britain to the Middle East via that route, so British reinforcements and supplies for the area had to travel around the Cape of Good Hope. For this reason, it was more convenient to reinforce General Sir Archibald Wavell's Middle East Command with troops from Australia, New Zealand and India. Nonetheless, even when Britain was threatened with invasion after the Battle of France and equipment was urgently required to re-equip the British Expeditionary Force after its losses in the Dunkirk evacuation, troops and supplies were still despatched to the Middle East Command. A convoy that departed the United Kingdom in August 1940 brought guns, stores, ammunition, and three armoured regiments, including the 7th Royal Tank Regiment, equipped with Matilda II tanks.^[8]
On 9 December 1940 the Western Desert Force under the command of Major General Richard O'Connor attacked the Italian position at Sidi Barrani. The position was captured, 38,000 Italian soldiers were taken prisoner, and the remainder of the Italian force was driven back.^[9] The Western Desert Force pursued the Italians into Libya, and the 7th Armoured Division established itself to the west of Bardia, cutting off land communications between the strong Italian garrison there and Tobruk.^[10] On 11 December, Wavell decided to withdraw the 4th Indian Division and send it to the Sudan to participate in the East African Campaign. Major General Iven Mackay's 6th Australian Division was brought forward from Egypt to replace it.^[11] Mackay assumed command of the area on 21 December 1940.^[12]