The Pembroke Royal Garrison Artillery was a part-time unit of the British Army that defended the coast of West Wales during both world wars.

In 1910, the Glamorgan and Pembroke Royal Garrison Artillery, which had been reorganised in the new Territorial Force (TF) two years earlier, was broken up into separate Glamorganshire and Pembrokeshire units.

[11][15][16] Together, these units were responsible for manning the following guns defending the anchorage at Milford Haven:[17] The Pembroke RGA mobilised in August 1914 in Western Coast Defences under the command of Major T.W.

[18] By October 1914, the campaign on the Western Front was bogging down into Trench warfare and there was an urgent need for batteries of Siege artillery to be sent to France.

The WO decided that the TF coastal gunners were well enough trained to take over many of the duties in the coastal defences, releasing Regular RGA gunners for service in the field, and 1st line RGA companies that had volunteered for overseas service had been authorised to increase their strength by 50 per cent.

[22][23][24] The battery left the UK on 31 March 1916 and landed at Le Havre on 1 April to join the British Expeditionary Force (BEF).

[24][25] In June the battery moved to join VII Corps, which was preparing for the Attack on the Gommecourt Salient in the forthcoming 'Big Push' (the Battle of the Somme).

Its main role was to bombard German trenches and strongpoints facing 56th (1/1st London) Division's attack frontage.

Also, 68th Siege Bty was ordered to change targets to support the 46th (North Midland) Division's failing attack on the other side of the salient.

68th Siege Bty was assigned to the massive fireplan for the Battle of the Selle on 17 October, when the 50th (Northumbrian) and 66th (2nd East Lancashire) Divisions made an assault crossing of the river, with German counter-attacks broken by the guns.

By now massive quantities of artillery were employed for each phase of the continuing offensive as Fourth Army attacked again and again through the autumn.

The offensive continued through the summer and autumn of 1917: the Battles of the Menin Road, Polygon Wood and Broodseinde were highly successful because of the weight of artillery brought to bear on German positions.

Artillery Observation Posts (OPs) were blinded by early morning mist and many were overrun along with the infantry in the forward zone.

[50][51][52][53] Next day the Germans continued their advance, and 68th Bde stood at Roise trying to stem the tide before pulling out after dark.

Preparations to cross it began on 11 October, with 68th Bde allocated to the II US Corps, which was operating under Fourth Army's command and had no artillery of its own.

The weather was misty, which hindered air and ground observation for counter-battery fire, but when the assault went in on the morning of 17 October the Selle itself was not much of an obstacle on II US Corps' front, and the objectives were taken.

Again, bad weather hindered air observation and CB work before the attack, but the barrage was deadly accurate.

As the regimental historian relates, "The guns of Fourth Army demonstrated, on 23rd October, the crushing effect of well co-ordinated massed artillery.

[25][35][46][26][74] In October the battery transferred back to Second Army, which had taken over direction of the faltering Third Ypres Offensive and fought a series of successful battles employing massive weight of artillery.

[25][35][75][77] In April 1918 the British artillery was concentrated for a planned offensive, but finding level sites for the howitzers was difficult in the wooded mountainous terrain.

By 1 November the Austrian army had collapsed and the pursuing British troops had left their heavy guns far in the rear.

The Pembroke RGA serving in the Milford Haven garrison was reduced from the three 2nd Line companies to just one, albeit with a slightly larger establishment of five officers and 100 men, and was to be kept up to strength with Regular recruits.

In April 1918 the Milford Haven Garrison comprised the following batteries:[7][16][90][91] After the TF was demobilised in 1919 the Pembroke RGA was placed in suspended animation.

When the TF was reconstituted as the Territorial Army (TA) in 1921, the unit was designated as the Pembrokeshire Coast Brigade, RGA, with the batteries numbered 184 and 185.

By this stage of the war many of the coast battery positions were manned by Home Guard detachments or in the hands of care and maintenance parties.

[111] The regiment lost its ancillary units: 14, 32 and 62 Coast Observer Detachments were disbanded in April, 106 was renumbered 33 the following month and left to join 530th (Princess Beatrice's) Coast Rgt on the Isle of Wight in July, while No 7 Plotting Room at Milford Haven reverted to Western Command.

Meanwhile 21st Army Group fighting in North West Europe was suffering a severe manpower shortage, particularly among the infantry.

It was disbanded in 1950, with some personnel transferring to 302 (Pembroke Yeomanry) Field Rgt and some to 109 Transport Column, Royal Army Service Corps.