The Battle of the Somme affected a broad swathe of the department, as the front line ran from north of Beaumont-Hamel down to Chilly, south of Chaulnes. The British held 14 miles of the front line from its northern end to the village of Maricourt while the French held the southern end, astride the valley of the River Somme.

The original intention had been for the French to hold a greater length of the front line, but the ferocious attack on Verdun in February 1916 engaged their strength and efforts and forced a reduction in their plans for the Somme. The British – originally the ‘junior partner’ in the planned offensive - therefore stretched their forces to cover a greater proportion of the line.

The professional British Army of 1914 had suffered such heavy losses that many of the troops arriving in the Somme in 1916 were volunteers, part of ‘Kitchener’s Army’ who left their civilian lives in response to the call for recruits. Newly trained, in 1916 they faced enemy fire for the first time.

The history of these men can be traced in memorials in Britain and here in the battlefields – and also, frequently, in local publications in their home towns.

The Allies’ aim was to break through the enemy’s lines of communications. The German army, under Falkenhayn’s overall control, held fortified positions along the ridges above the River Ancre and the River Somme. The Roman road leading north from Albert to Bapaume was a crucial supply route to be seized.

The areas behind the front lines in the Somme were busy with troops and supplies, positions were strengthened and troops prepared for battle. Eventually the combined armies – English, French and German – numbered around a million men, with 200,000 horses.

Bad weather delayed the opening attack and forced the British Army to extend its heavy preliminary bombardment to a full week. Unfortunately, its effects were less than anticipated: the German underground shelters and the protective screens of barbed wire were largely unbroken.

The battle began at 7.30 am on 1 July 1916, a few moments after the explosion of several huge mines (‘Hawthorn’ at Beaumont-Hamel, ‘Lochnagar’ at La Boisselle and ‘the Tambour’ at Fricourt are three whose sites can still be seen). Protected by their artillery barrage, the British and French infantry advanced from their trenches with, two hours later, a further French attack south of the river Somme as a diversion.

By the evening, the French Army (General Fayolle) had reached its primary objectives, capturing the German front line south of the Somme and taking Curlu and Hardecourt north of the river.

The British Army, however, suffered a disastrous first day of battle. The new and inexperienced troops (General Allenby’s Third Army and General Rawlinson’s Fourth Army) attacked the ridge at Thiepval and at Beaumont-Hamel but without success. The 36th (Ulster) Division broke through briefly but was isolated and had to withdraw. South of La Boisselle and at Fricourt, the German line was pierced in a very few places.

The losses on 1 July were the British Army’s worst ever for a single day: 60,000 casualties, of whom almost 20,000 were killed. Many battalions lost over half their men; the Newfoundlanders suffered around 70 % casualties in thirty minutes at Beaumont-Hamel.

Despite this terrible setback, the battle continued and made slow and uneven progress through July. The South African memorial at Longueval and the Australian memorial at Pozières mark hard-won triumphs, while the villages of Fricourt and Mametz were gains not matched elsewhere. The French advance was halted two kilometres from Péronne by the wide marshes of the River Somme. In August the combined French and British forces launched costly and limited attacks which won control of the 2nd German line at Pozières, Bazentin, Maurepas, Hem and Herbécourt. A fresh offensive in September finally achieved the capture of Thiepval.

Also in September, the British launched the first-ever tank attack and took Flers, Martinpuich and Courcelette. The French occupied Bouchavesnes, Rancourt, Cléry-sur-Somme and Deniécourt, Vermandovillers and Chilly, but the German front remained unbroken. For the French, General Micheler’s Tenth Army joined the attack along a 20-kilometre front to the south.

Early in October the third German line was captured, but the British were brought to a halt close to Courcelette and Le Sars, on the Albert-Bapaume road. On their right, the French suffered heavily (Sailly-Saillisel, St.Pierre-Vaast, Rancourt), and to the west the village of Beaumont-Hamel was not captured until the middle of November.

Heavy autumn rain overwhelmed the land: men, animals and weapons became bogged down in the thick clinging mud, the battle ended and both sides set about replenishing their fighting units and equipment. During the four and a half months of battle, the British troops had advanced approximately 12 kilometres, the French – with their smaller numbers - between 5 and 8 kilometres.

It is calculated that around three million men were involved in the fighting during the Battle of the Somme; some 1,200,000 were killed, wounded or missing in action. The Allied objectives, defined six months before the battle was launched, were not reached.

The full effect of losses was felt particularly severely among the communities where recruiting in 1914 had attracted groups of men to enlist together, leaving their ordinary civilian life to join ‘Kitchener’s Army’. These ‘Pals Battalions’ of friends or workmates – from a street, a factory, an office or a professional establishment - suffered heavily on 1 July 1916, and are commemorated in France along the front line of that opening day and in their own communities in Britain.

Yet the battle was successful in drawing German forces away from Verdun: despite the heavy toll of Allied dead in 1916 (the battle of Verdun as well as the Somme), the German leadership declared at the end of the year that its army ‘could not survive another year like that’.