12th Mechanized Brigade ( United Kingdom ) The 12th Mechanized Brigade is a regular British Army brigade which has been in existence since 1899 and now forms part of 3rd Mechanised Division . History . Second Boer War . The brigade was first formed in December 1899 as 12th Infantry Brigade and saw action at the Battle of Rensburg , Battle of Norval ' s Point , Battle of Biddulph ' s Berg and Battle of Slabbert ' s Nek . First World War . During the First World War , the 12th Infantry Brigade , a regular army formation , was assigned to the 4th Infantry Division . It was dispatched to France , crossing the English Channel on 22 August 1914 , as part of the British Expeditionary Force ( BEF ) and saw action in the First Battle of the Marne beginning in September 1914 . It then spent much of the rest of the conflict engaged in trench warfare . Brigade units during the First World War included : From early November 1915 until February 1916 the 12th Brigade was swapped with the 107th Brigade of the 36th ( Ulster ) Division . Second World War . During the Second World War , except for a few brief periods of detachment , the brigade formed part of 4th Infantry Division . It was part of the British Expeditionary Force and took part in the Dunkirk evacuation in May 1940 . It moved to North Africa in February 1943 to take part in the later stages of the Tunisia Campaign and saw action at the Battle of Oved Zara , the Battle of Medjez Plain and the Battle of Tunis . It then took part in the Italian Campaign , moving to Naples in February 1944 and saw further action at the Fourth Battle of Monte Cassino . By October 1944 the Division was taking part in Eighth Army ' s battle on the Gothic Line but was withdrawn in November to spend the rest of the war in Greece , part of the Allied force tasked to prevent civil unrest as rival factions attempted to fill the political vacuum when the Germans withdrew from the country . Brigade units during the Second World War included : Commanders during the Second World War included : Post - 1945 . The Brigade was disbanded in March 1947 , but reformed from 91 Lorried Infantry Brigade in April 1956 . After being briefly converted to " Task Force Delta " in the late 1970s , the brigade was reinstated in 1981 . Moved to 1st Armoured Division , it remained , with a spell under HQ 3rd Armoured Division during Operation Granby , until disbandment under Options for Change . Following the Strategic Defence Review in 1998 , the brigade was reformed in mechanized form under 3rd Armoured Division at Aldershot : it relocated to Ward Barracks in Bulford in February 2004 . Present . The brigade headquarters , with two battle groups - the 1st Battalion The Royal Anglian Regiment and the 1st Battalion The Grenadier Guards - deployed to Afghanistan in 2007 to form the headquarters and main infantry combat units of Task Force Helmand as a part of the NATO International Security Assistance Force . Under Army 2020 , its headquarters will remain at Bulford and it will form part of the Reaction Force . It will be renamed 12th Armoured Infantry Brigade . Army 2020 . Under the Army 2020 reform the 12th Mechanized Brigade will be renamed as 12th Armoured Infantry Brigade and will form part of the 3rd Division , the Reaction Force , under plans confirmed by the Secretary of State for Defence , Phillip Hammond , on 5 July 2012 . Brigade Commanders . Recent commanders have included :