The Royal Green Jackets (RGJ) was an infantry

Infantry

Infantrymen are soldiers who are specifically trained for the role of fighting on foot to engage the enemy face to face and have historically borne the brunt of the casualties of combat in wars. As the oldest branch of combat arms, they are the backbone of armies...

 regiment

Regiment

A regiment is a major tactical military unit, composed of variable numbers of batteries, squadrons or battalions, commanded by a colonel or lieutenant colonel...

 of the British Army

British Army

The British Army is the land warfare branch of Her Majesty's Armed Forces in the United Kingdom. It came into being with the unification of the Kingdom of England and Scotland into the Kingdom of Great Britain in 1707. The new British Army incorporated Regiments that had already existed in England...

, one of two "large regiments"

Large regiment

A large regiment is a multi-battalion infantry formation of the British Army. First formed in the 1960s, large regiments are the result of the amalgamation of three or more existing single-battalion regiments, and perpetuate the traditions of each of the predecessor units.-Origins:Following the...

 within the Light Division

Light Division

The Light Division was a light infantry Division of the British Army formed in the early 19th Century. It can trace its origins to the Light Companies which had been formed to move at speed over inhospitable terrain and protect the main forces by skirmishing tactics...

 (the other being The Light Infantry

The Light Infantry

The Light Infantry was an infantry regiment of the British Army, part of the Light Division. It was formed on 10 July 1968 as a "large regiment" by the amalgamation of the four remaining light infantry regiments of the Light Infantry Brigade:...

).
It was formed in 1966 by the amalgamation of the three separate regiments of the Green Jackets Brigade

Green Jackets Brigade

The Green Jackets Brigade was an administrative formation of the British Army from 1948 to 1968. The Brigade administered the English rifle regiments. The designation "Green Jackets" was derived from their rifle green tunics indicating their status as rifles....

:

• 1st Green Jackets, (43rd and 52nd)
  Oxfordshire and Buckinghamshire Light Infantry
  The Oxfordshire and Buckinghamshire Light Infantry was an infantry regiment of the British Army.The regiment was formed as a consequence of Childers reforms, a continuation of the Cardwell reforms, by the amalgamation of the 43rd Regiment of Foot and the 52nd Regiment of Foot , forming the 1st...
  
  
• 2nd Green Jackets, The King's Royal Rifle Corps
  King's Royal Rifle Corps
  The King's Royal Rifle Corps was a British Army infantry regiment, originally raised in colonial North America as the Royal Americans, and recruited from American colonists. Later ranked as the 60th Regiment of Foot, the regiment served for more than 200 years throughout the British Empire...
  
  
• 3rd Green Jackets, The Rifle Brigade

There were also two Territorial Army battalions made up as follows

• 4th(V) Bn Royal Green Jackets - formed from the remnants of the Rangers (KRRC), London Rifle Brigade, Tower Hamlets Rifles, Queens Westminsters, Queen Victoria's Rifles and Civil Service Rifles.
• 5th(V) Bn Royal Green Jackets - formed from the 4th Bn the Oxfordshire & Buckinghamshire Light Infantry (TA) and the Buckinghamshire Battalion of the Ox & Bucks Light Infantry

In 1992 1st RGJ was disbanded and 2/RGJ and 3/RGJ renumbered 1/RGJ and 2/RGJ respectively.

The last ever Royal Green Jackets unit was the London Oratory CCF who were rebadged as Irish Guards

Irish Guards

The Irish Guards , part of the Guards Division, is a Foot Guards regiment of the British Army.Along with the Royal Irish Regiment, it is one of the two Irish regiments remaining in the British Army. The Irish Guards recruit in Northern Ireland and the Irish neighbourhoods of major British cities...

 in 2010.

Their motto was Celer et Audax (Latin

Latin

Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

: "Swift and Bold").