On 31st July 1917, Field Marshal Haig launched the offensive which became known as the 3rd Battle of Ypres, or, more notoriously, as the Battle of Passchendaele. The 38th (Welsh) Division, including the 1st and 2nd Gwents, was ordered to attack and hold Pilkem Ridge and Iron Cross Ridge north of Ypres. In spite of facing heavy resistance from elite German Guards, the division took its objectives. The Gwents found themselves having to storm well-established machine-gun posts and pillboxes. The following day they faced a heavy bombardment and counter-attack but held their lines. The price was again very high, with the two battalions suffering 550 casualties, a price that became all the harder to bear as it became apparent that the offensive was following the familiar pattern of becoming bogged-down in the face of heavy German reinforcements. As the battle wore on, the Gwents’ casualties mounted. 200 more were sustained in an attack on Langemark in August and another 50 in a major raid on German dug-outs in the final days of the battle in November.
No sooner had 3rd Ypres ended than another offensive had begun. On 20th November the British army launched an attack at Cambrai, using tanks en masse for the first time. Initially they met with great success and much land was taken. At the northern end of the battlefield, however, the Germans were still in possession of high land around Bourlon Wood. On 23rd November, the the “bantams” of the 3rd Gwents (12th South Wales Borderers), along with the 19th Royal Welsh Fusiliers and 17th Welsh, were ordered to dislodge the Germans. In three days of heavy fighting, including bayonet charges within the wood itself, ground was won, lost and won again. The Welsh troops were finally successful in taking the wood and the village beyond it. Once again, a heavy price had been paid. 133 officers men from the 3rd Gwents were dead or missing, with a further 255 wounded. Cambrai ultimately failed to bring the breakthrough it had promised, but this was certainly no fault of the 3rd Gwents. A veteran of Bourlon Wood, Sergeant William Parkes, was to live to be the last survivor of the South Wales Borderers. He died in the USA in 2002 at the age of 106.
The 2nd South Wales Borderers had followed the tanks in the initial assault and were amongst the units holding the newly-won positions when, on 30th November, the Germans launched a strong counter-attack. The battalion contributed significantly to the defence of the line, but by the time it was relieved on 2nd December, it had been reduced to just four officers and 73 men.