Early Allied amphibious operations during the war were hampered by poor organisation and control of the landing beaches.
In 1941 the Royal Naval beach parties, which were the forerunners to the Royal Naval Commandos, were raised.

The first Royal Naval Commandos were formed from these beach parties shortly after Operation Ironclad, the initial Allied landings on Madagascar to capture the Vichy French-held port of Diego Suarez in early May 1942.
During this operation specially-trained Royal Navy beach parties were landed along with the first wave of assault troops in order to organise the beachheads and control the landings.
The success of these parties led to the decision to form the Royal Naval Commandos and over the course of 1942–43 personnel were selected and training undertaken at HMS Armadillo at Ardentinny and then later at the commando school at Achnacarry in Scotland.

In the end 22 Royal Naval Commando units were raised, designated 'A' through to 'W' (although there was no 'I' Commando), each with its own distinctively coloured lanyard worn on the left shoulder when wearing general British army battledress.
Of note, 'W' Commando was largely formed from personnel drawn from the Royal Canadian Navy.
Each unit was roughly equivalent in size to a company.
They were commanded by an officer of the rank of lieutenant commander or commander and consisted of 10 officers and 65 ratings organised into three parties, each of 25 men.
Early Allied amphibious operations during the war were hampered by poor organisation and control of the landing beaches. In 1941 the Royal Naval beach parties, which were the forerunners to the Royal Naval Commandos, were raised.
The first Royal Naval Commandos were formed from these beach parties shortly after Operation Ironclad, the initial Allied landings on Madagascar to capture the Vichy French-held port of Diego Suarez in early May 1942. During this operation specially-trained Royal Navy beach parties were landed along with the first wave of assault troops in order to organise the beachheads and control the landings. The success of these parties led to the decision to form the Royal Naval Commandos and over the course of 1942–43 personnel were selected and training undertaken at HMS Armadillo at Ardentinny and then later at the commando school at Achnacarry in Scotland.
In the end 22 Royal Naval Commando units were raised, designated 'A' through to 'W' (although there was no 'I' Commando), each with its own distinctively coloured lanyard worn on the left shoulder when wearing general British army battledress. Of note, 'W' Commando was largely formed from personnel drawn from the Royal Canadian Navy. Each unit was roughly equivalent in size to a company. They were commanded by an officer of the rank of lieutenant commander or commander and consisted of 10 officers and 65 ratings organised into three parties, each of 25 men.
Royal Naval Commandos