172nd (2/1st South Lancashire) Brigade

The 172nd (2/1st South Lancashire) Brigade was an infantry brigade of the British Army that served during the First World War. As its title indicates, it was formed as a second-line unit of the 1st South Lancashire Brigade. Part of the 57th (2nd West Lancashire) Division, it saw action on the Western Front. The brigade's constituent battalions were primarily composed of Territorial Force units. It participated in several major battles and engagements, including actions during the German spring offensive of 1918 and the subsequent Allied counter-offensives. Following the Armistice in November 1918, the brigade was involved in occupation duties before being demobilized. The "2/1st" designation indicates the brigade was the second-line duplicate of the 1st South Lancashire Brigade, formed to accommodate the influx of volunteers at the start of the war. This structure allowed trained soldiers to be assigned to the first-line unit (the original brigade), while newer recruits could be trained and prepared in the second-line unit before potentially being transferred to the front lines. The brigade's association with the South Lancashire Regiment reflects the geographic recruitment area and the regimental affiliation of many of its soldiers.