They marched to war, many of them wearing kilts and to the skirl of the bagpipes, the highest concentration of Scottish troops to fight in a single First World War battle. 

Tragically, many would breathe their last as the Battle of Arras raged around them. Of the 159,000 Allied casualties, almost one-third were Scots.

Their final resting place is among the rows of pristine white headstones in cemeteries dotted around northern France, every one meticulously tended by the Commonwealth War Graves Commission and each stone identical apart from their poignant inscription. 

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Now the mammoth and the continuing task of recovering the war dead, piecing together their identities and honouring them and their comrades in cemeteries where even each blade of grass seems to stand to attention, is to be revealed to Northern France battlefield visitors for the first time.

A new Commonwealth War Graves Commission visitor centre, the CWGC Experience, located close to a small cemetery which holds the last earthly remains of 331 Allied soldiers in Beaurains, France, will be officially opened by HRH The Princess Royal on Tuesday. 

The centre, at the heart of the area which encompassed the Battle of Arras, will give battlefield visitors a fascinating insight into the ongoing work that makes remembrance of the 1.7 million Commonwealth war dead possible.

As well as highlighting the endless gardening and maintenance work required to ensure the white stones gleam and the weeds are kept at bay, the centre will reveal how, even now, CWGC staff are carrying out sensitive work to identify and bury the war dead. 

Although active searching of the battlefields ended shortly after the two world wars, each year land bitterly fought over generations ago yields poignant reminders of the human cost of battle.

Around 40 remains are discovered each year, many uncovered as the result of French villages and towns expanding into what were once battlefield sites.

Incredibly, even if remains continue to be found at that rate, it’s estimated that it would take 4,300 years to find all of the 155,000 missing – a chilling reminder of the scale of wartime losses.

Once remains are found, a meticulous investigation begins in an attempt to establish their nationality, identity, cause of death and to track down remaining family members.

Each Allied soldier is then laid to rest in a CWGC cemetery alongside his comrades, with military honours.

Visitors to the new centre will also see the commission’s team of craftsman carrying out age-old skills of carving stones and creating and repairing metalwork for memorials and cemetery features. 

Dr Lucy Kellett, interpretation officer at CWGC, said: “We wanted to tell another side of the cemeteries’ story.

People come here to see the pristine cemeteries and the uniform rows of headstones that give the cemeteries such visual impact. 

“But we wanted to convey the industry and effort that goes into making them this way.” She added: “People think of the Battle of Arras as Scotland’s war, and the names that can be seen on the headstones reflect that message.”

Scottish regiments took part in most of the First World War’s key battles. The retreat from Mons in 1914 saw just 70 men and a junior officer remaining standing from the 1,000 strong 1st Royal Scots Fusiliers, while the 9th Black Watch lost 680 officers and men. Only 250 out of 950 men that made up the 6th Cameronians emerged unhurt. 

At Loos the following year, 36 out of the 72 attacking battalions were Scottish. More than half of the 12 battalions which registered more than 500 casualties, were Scottish.

However, the Battle of Arras, when British troops attacked German defences close to the city of Arras in Northern France, was regarded as a particularly Scottish tragedy. The offensive began on April 9, 1917, and included the greatest concentration of Scots of any of the war’s set-piece battles, with 44 out of the 120 infantry battalions made up of Scots.

Alongside them were seven Canadian battalions with Scottish heritage, including The Canadian Scottish and The Newfoundland Regiment. There were also Scottish-based regiments from Tyneside and London. By the time the battle came to an end on May 16, one-third of the 159,000 British casualties were Scottish.

Dr Kellet said the new visitor centre would help “humanise” the work of the CWGC and show the process of remembering the war dead from a century ago is an ongoing task. 

“Our job is very much dealing with the dead, but we want to remind visitors that people are at the heart of what we do, and for them to understand what it means for us to work here. It is a huge privilege to be able to contribute to something so meaningful.”

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More than 780,000 Commonwealth service personnel of the two world wars are commemorated by the CWGC in France and Belgium in cemeteries and at memorials. Just under half of the 320,000 missing servicepersons have not yet been recovered. 

Victoria Wallace, CWGC’s director general, said: “For over 100 years, the CWGC has worked to care for our war dead. I am delighted that we can now share with the public the skills, the dedication and the craftsmanship of our fantastic team, working on the Western Front and around the world. We hope young people, in particular, will gain inspiration from this extraordinary legacy of care.”