Three UK based Army Commando units, Nos. 7, 8, and 11 Commandos, were initially combined within 'Force Z' for operations initially envisaged against Rhodes in the Eastern Mediterranean. Other elements of the Force included a number of men from No.3 Commando and the Canoe section of No.8 (Guards) Commando. They sailed from the Isle of Arran on the 31st January 1941, and arrived at Suez on the 7th March.
A further three Commandos had been raised in the Middle East and were numbered 50, 51 and 52 (Middle East) Commandos. However these United Kingdom based and Middle East raised Commando groups were quite distinct, operating under different commands, and having very different structures. By the time Force Z arrived at Suez it had been decided that the designation Force Z should be changed to Layforce (in deference to its Commanding Officer - Robert E Laycock), and for security reasons all reference to the word 'Commando' should be dropped.The units were therefore renamed as follows: 'A' Battalion Layforce (Lt. Col. J.B. Colvin) - 7 Commando 'B' Battalion Layforce (Lt Col. D.R. Daly) - 8 Commando 'C' Battalion Layforce (Lt. Col. R.R.N. Pedder) - 11 Commando
Three days later the force arrived at Geneifa, the place to which No.50 and No.52 Middle East Commando had recently returned from Crete and Operations in East Africa respectively. Both of these Middle East Commandos were amalgamated and joined Layforce as 'D' Battalion Layforce (Lt Col. G.A.D. Young RE).
Read on from the document below about Layforce.