129th Infantry Brigade (United Kingdom)

South Western Brigade 129th (South Western) Brigade 129th Infantry Brigade
43rd Division insignia, World War II
Active	1908-1919 1920-1946 1947-1968
Country	United Kingdom
Branch	Territorial Army
Type	Infantry
Size	Brigade
Part of	43rd (Wessex) Infantry Division
Engagements	Operation Overlord Operation Market Garden Battle of the Bulge Operation Blackcock Operation Veritable

The 129th Infantry Brigade was an infantry brigade of the British Army that served during both the First and Second World Wars. In both wars the brigade was part of 43rd (Wessex) Infantry Division.

The brigade was originally formed in 1908 in the Territorial Force as the South Western Brigade attached to the Wessex Division. It was composed of four Volunteer battalions, two, the 4th and 5th, of the Prince Albert's (Somerset Light Infantry), the 4th Battalion of the Dorsetshire Regiment and one, the 4th Battalion, of the Duke of Edinburgh's (Wiltshire Regiment).

The division was mobilised in August 1914, shortly after the outbreak of the Great War. The division was sent overseas to India to free up Regular Army troops for service on the Western Front in France and Belgium. In 1915 the division was numbered as the 43rd (Wessex) Division and the brigade became the 129th (1/1st South Western) Brigade. However, the division, and the brigade, never saw action and was disbanded later in the war but many of the divisions units saw service with mainly British Indian Army brigades and divisions.

The Territorial Force was disbanded shortly after the end of the Great War. It was, however, reformed as the Territorial Army in 1920 and both the 43rd Division and the brigade were also reformed. The brigade was now known as 129th (South Western) Infantry Brigade, composed of the same battalions it had before the Great War and this was the composition of the brigade for most of the inter-war years.