Mersa Matruh in the context of "Second Battle of El Alamein"

The Italian invasion of Egypt (Operazione E) was an offensive in the Second World War from Italian Libya, against British, Commonwealth and Free French in the neutral Kingdom of Egypt. The invasion by the Italian 10th Army (10ª Armata) ended border skirmishing on the frontier and began the Western Desert Campaign (1940–1943) proper. The Italian strategy was to advance from Libya along the Egyptian coast to seize the Suez Canal. After numerous delays, the scope of the offensive was reduced to an advance as far as Sidi Barrani and the defeat of any British forces in the area.

The 10th Army advanced about 65 mi (105 km) into Egypt against British screening forces of the 7th Support Group (7th Armoured Division) the main force remaining in the vicinity of Mersa Matruh, the principal British base in the Western Desert. On 16 September 1940, the 10th Army halted and took up defensive positions around the port of Sidi Barrani. British casualties were 40 men killed and the Italians suffered 120. The army was to wait in fortified camps, until engineers had built the Via della Vittoria (Victory Road) along the coast, an extension of the Libyan Via Balbia. The Italians began to accumulate supplies for an advance against the 7th Armoured Division and the 4th Indian Division at Mersa Matruh, about 80 mi (130 km) further on.

The Battle of Mersa Matruh was fought from 26 to 29 June 1942, following the defeat of the Eighth Army (General Sir Claude Auchinleck) at the Battle of Gazala and was part of the Western Desert Campaign of the Second World War. The battle was fought with the German–Italian Panzer Army Afrika (Panzerarmee Afrika (Generalfeldmarschall Erwin Rommel). The Eighth Army comprised X Corps and XIII Corps.

The battle was fought during the pursuit by the Panzerarmee of the Eighth Army as it retreated into Egypt. Rommel intended to defeat in detail (one after the other) the British infantry formations, before they had a chance to regroup. The fortress port of Mersa Matruh and 6,000 prisoners were captured, along with a great deal of supplies and equipment. The Axis cut off the line of retreat of X Corps and XIII Corps but was too weak to stop the British from breaking out.

Operation Compass (also Italian: Battaglia della Marmarica) was the first large British military operation of the Western Desert Campaign (1940–1943) during the Second World War. British metropolitan, Imperial and Commonwealth forces attacked the Italian and Libyan forces of the 10th Army (Marshal Rodolfo Graziani) in western Egypt and Cyrenaica, the eastern province of Libya, from December 1940 to February 1941.

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 troops in fortified posts around Sidi Barrani in Egypt and in Cyrenaica to the west. The WDF swiftly defeated the Italians in their fortified posts and at Sidi Barrani, forced the rest of the 10th Army out of Egypt and captured the ports along the Cyrenaican coast in Libya. The 10th Army was cut off as it retreated towards Tripolitania at the Battle of Beda Fomm, the remnants being pursued to El Agheila on the Gulf of Sirte.