The Royal Military Police is fiercely proud of its "first in, last out" tradition that it established after the Second World War.

It has four primary functions - to provide operational support to the Army, prevent crime, maintain military discipline, and provide advice and information to the military and the public.

The RMP can trace its roots back as far as 1241 when William of Cassingham was appointed a military Sergeant of the Peace by King Henry III.

It is one of the oldest sections of the British Army.

In the 19th Century, the military police worked under two separate sections - the Military Mounted Police (MMP), established in 1877, and the Military Foot Police (MFP), set up in 1882.

The MMP and MFP were two distinct entities, which essentially worked for the same organisation.

It was not until 1915 that the two police units worked together in the Battle of Neuve Chapelle, focusing on traffic and straggler control.

They continued to be regular features in the First World War and played a part in battles at Mons, the Marne, Ypres and the Somme.

A total of 375 military police were killed and 477 decorations were given in recognition of bravery.

Finally, in 1926, the two factions were amalgamated into the Corps of Military Police (CMP).

The CMP played an important part in the Second World War and served in France, Italy, North Africa, the Far East and Africa. More precisely, they played roles at Monte Cassino, Dunkirk, Alamein, Malta, Arnhem and on the beaches of Normandy.

After the two world wars, a Role of Honour was established, bearing the names of 912 service personnel for their courage and devotion to duty.

It was then that the military police established the tradition of being "first in, last out" in times of conflict.

At the time, General Sir Myles Dempsey described the corps: "The military policeman became so well known a figure on every road to the battlefield that his presence became taken for granted.

"Few soldiers as they hurried over a bridge, which was a regular target for the enemy, gave much thought to the man whose duty it was to be there for hours on end, directing traffic and ensuring its rapid passage."

In 1946, King George VI granted the "Royal" prefix to the military police, again in recognition of its valiant war efforts. Its motto is Exemplo Ducemis: by example we lead.

More recently, the RMP has played an important part in Northern Ireland, where it has worked in collaboration with the Royal Ulster Constabulary since 1969.

It has also served in Zimbabwe - then Rhodesia - the Falklands, and provided support in the first Gulf war, in 1991.

Throughout the 1990s, the RMP worked under UN and Nato command in the former Republic of Yugoslavia.

In the wake of the second Gulf war earlier this year, the RMP has been working closely with Iraqis, training local police.