Third Army (United Kingdom) in the context of "Battle of Cambrai (1917)"

The Nivelle offensive (16 April – 9 May 1917) was a Franco-British operation on the Western Front in the First World War which was named after General Robert Nivelle, the commander-in-chief of the French metropolitan armies, who led the offensive. The French part of the offensive was intended to be strategically decisive by breaking through the German defences on the Aisne front within 48 hours, with casualties expected to be around 10,000 men. A preliminary attack was to be made by the French Third Army at St Quentin and the British First, Third and Fifth armies at Arras, to capture high ground and divert German reserves from the French fronts on the Aisne and in Champagne. The main offensive was to be delivered by the French on the Chemin des Dames ridge (the Second Battle of the Aisne). A subsidiary attack was to be made by the Fourth Army (the Third Battle of Champagne). The final stage of the offensive was to follow the meeting of the British and French armies, having broken through the German lines, to pursue the defeated German armies towards the German frontier.

The Franco-British attacks were tactically successful; the French Third Army of Groupe d'armées du Nord (GAN, Northern Army Group) captured the German defences west of the Hindenburg Line (Siegfriedstellung) near St Quentin from 1 to 4 April, before further attacks were repulsed. The British Third and First armies achieved the deepest advance since trench warfare began, along the Scarpe river in the Battle of Arras, which inflicted many casualties on the Germans, attracted reserves and (specifically the four Canadian divisions of the First Army) captured Vimy Ridge to the north. The main French offensive on the Aisne began on 16 April and also achieved considerable tactical success but the attempt to force a strategically decisive battle on the Germans was a costly failure and by 25 April the main offensive had been suspended.

The first day on the Somme (1 July 1916) was the beginning of the Battle of Albert (1–13 July) the name given by the British to the first two weeks of the Battle of the Somme (1 July–18 November) in the First World War. Nine corps of the French Sixth Army and the British Fourth and Third armies attacked the German 2nd Army (General Fritz von Below). The attack was from Foucaucourt south of the Somme, northwards across the Somme and the Ancre to Serre and Gommecourt, 2 mi (3.2 km) beyond, in the Third Army area. The objective of the attack was to capture the German first and second defensive positions from Serre south to the Albert–Bapaume road and the first position from the road south to Foucaucourt.

The German defence south of the road mostly collapsed and the French had complete success on both banks of the Somme, as did the British from Maricourt on the army boundary with the French northwards. XIII Corps took Montauban and reached all its objectives, XV Corps captured Mametz and isolated Fricourt. The III Corps attack on both sides of the Albert–Bapaume road was a disaster, making only a short advance south of La Boisselle, where the 34th Division suffered the most casualties of any Allied division on 1 July. Further north, X Corps captured part of the Leipzig Redoubt (an earthwork fortification), failed opposite Thiepval and had a great but temporary success on the left flank, where the German front line was overrun and Schwaben and Stuff redoubts captured by the 36th (Ulster) Division.

The Battle of Arras, also known as the Second Battle of Arras, was a British offensive on the Western Front during the First World War. From 9 April to 16 May 1917, British troops attacked German defences near the French city of Arras on the Western Front. The British achieved the longest advance since trench warfare had begun, surpassing the record set by the French Sixth Army on 1 July 1916 in the First day on the Somme. The British advance slowed in the next few days and the German defence recovered. The battle became a costly stalemate for both sides and by the end of the battle, the British Third Army and the First Army had suffered about 160,000 casualties and the German 6th Army about 125,000.

For much of the war, the opposing armies on the Western Front were at a stalemate, with a continuous line of trenches from the Belgian coast to the Swiss border. The Allied objective from early 1915 was to break through the German defences into the open ground beyond and engage the numerically inferior German Army (Westheer) in a war of movement. The British attack at Arras was part of the Anglo-French Nivelle Offensive, the main part of which was the Second Battle of the Aisne 50 mi (80 km) to the south. The aim of the French offensive was to break through the German defences in forty-eight hours. At Arras the Canadians were to capture Vimy Ridge, dominating the Douai Plain to the east, advance towards Cambrai and divert German reserves from the French front.