[8] However, after the defeat of the main Boer field armies and the development of guerrilla warfare, all the divisions and brigades were broken up to form ad hoc 'columns' and garrisons.

[14] In the Expeditionary Force established by the Haldane reforms, 12th Brigade at Colchester and later at Dover became part of 4th Division, and remained so until the outbreak of World War I.

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.

The brigade remained in the United Kingdom for the next two years, preparing and training to repel Operation Sea Lion, the German invasion of England, although that never arrived.

By October 1944 the 4th Division was taking part in the British Eighth Army's battle on the Gothic Line but was withdrawn in November to spend the rest of the war in Greece, part of the Allied force tasked to prevent civil unrest as rival factions attempted to fill the political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.

[8] Following the Strategic Defence Review in 1998, the brigade was reformed in mechanized form under 3rd Mechanised Division at Aldershot Garrison: it relocated to Ward Barracks in Bulford Camp in February 2004.