In accordance with the Territorial and Reserve Forces Act 1907 which brought the Territorial Force into being, the TF was intended to be a home defence force for service during wartime and members could not be compelled to serve outside the country. However, on the outbreak of war on 4 August 1914, many members volunteered for Imperial Service. Therefore, TF units were split into 1st Line and 2nd Line units. 2nd Line units performed the home defence role, although in fact most of these were also posted abroad in due course.
1/1st Glamorganshire
The 1st Line battery was embodied with the South Wales Mounted Brigade on 4 August 1914 at the outbreak of the First World War. The brigade assembled at Hereford and moved to East Anglia by the end of August 1914. It joined the 1st Mounted Division in August 1914, replacing 1st South Midland Mounted Brigade which moved to 2nd Mounted Division. In December 1915, the battery was re-equipped with four 18 pounders. In March 1916, the South Wales Mounted Brigade was dismounted and left for Egypt. The brigade was replaced in the 1st Mounted Division by 2/1st Eastern Mounted Brigade and the battery remained with the division until August 1916. 2/IV London Brigade, RFA of 58th Division was broken up in July 1916 when it batteries were posted to 2/I and 2/II London Brigades, RFA . The brigade was reformed for 58th Division in August 1916 as CCXCIII Brigade, RFA with two gun batteries provided by 1/1st Shropshire RHA and 1/1st Glamorganshire RHA and two howitzer batteries and D. The Brigade Ammunition Column had been redundant since the South Wales Mounted Brigade had left, so the men were transferred to the 58th Divisional Trench Mortar Brigade. CCXCIII brigade landed at Le Havre on 22 January 1917. On 6 February 1917, D Battery was split between D/CCXC Battery and D/CCXCI Battery; the remainder of the brigade became CCXCIII Army Field Artillery Brigade, RFA, now with two batteries of six 18 pounders and one of four 4.5" howitzers. At the Armistice, the battery was still with CCXCIII Army Brigade, RFA serving as Army Troops with the First Army.
2/1st Glamorganshire
Glamorganshire RHA formed a 2nd line, 2/1st Glamorganshire Battery, RHA, in 1915. The pre-war Territorial Force infantry divisions were generally supported by four field artillery brigades. These were numbered I, II, III and IV within each division and consisted of three gun brigades and a howitzer brigade. Artillery for 2nd Line divisions were formed in a similar manner, with a fractional designation, for example the 2/III North Midland Brigade, RFA for 59th Division. Territorial Force artillery brigades were later numbered in a consecutive sequence, and batteries lettered, so for the above example, CCXCVII Brigade, RFA with A, B and C batteries. The battery, equipped with four 18 pounders, joined CCXCVII Brigade, RFA in 59th Division in Ireland in early May 1916 and became D/CCXCVII Battery. On 10 July 1916, the battery transferred to CCXCVIII Brigade, RFA as C/CCXCVIII Battery. At this point, CCXCVIII Brigade consisted of three 2nd Line RHA batteries: 2/1st Hampshire as A Battery, 2/1st Essex as B Battery and 2/1st Glamorganshire as C Battery. In January 1917, the division returned to England. Before leaving Ireland, the battery was broken up: one section joined A/CCXCVIII Battery and the other joined B/CCXCVIII Battery to make them up to six 18 pounders each.
Post war
The battery not reconstituted in the Territorial Force in 1920.
