The Battle of Verdun (French: Bataille de Verdun [bataj də vɛʁdœ̃]; German: Schlacht um Verdun [ʃlaxt ʔʊm ˈvɛɐ̯dœ̃]) was fought from 21 February to 18 December 1916 on the Western Front in France. The battle was the longest of the First World War and took place on the hills north of Verdun-sur-Meuse. The German 5th Army attacked the defences of the Fortified Region of Verdun (RFV, Région Fortifiée de Verdun) and those of the French Second Army on the right (east) bank of the Meuse. Using the experience of the Second Battle of Champagne in 1915, the Germans planned to capture the Meuse Heights, an excellent defensive position, with good observation for artillery-fire on Verdun. The Germans hoped that the French would commit their strategic reserve to recapture the position and suffer catastrophic losses at little cost to the German infantry.

Poor weather delayed the beginning of the attack until 21 February but the Germans captured Fort Douaumont in the first three days. The advance then slowed for several days, despite inflicting many French casualties. By 6 March, 20+1⁄2 French divisions were in the RFV and a more extensive defence in depth had been organised. Philippe Pétain ordered there to be no retreat and that German attacks were to be counter-attacked, despite this exposing French infantry to the German artillery. By 29 March, French guns on the west bank had begun a constant bombardment of Germans on the east bank, causing many infantry casualties. The German offensive was extended to the west bank of the Meuse to gain observation and eliminate the French artillery firing over the river but the attacks failed to reach their objectives.

In early May, the Germans changed tactics again and made local attacks and counter-attacks; the French recaptured part of Fort Douaumont but the Germans ejected them and took many prisoners. The Germans tried alternating their attacks on either side of the Meuse and in June captured Fort Vaux. The Germans advanced towards the last geographical objectives of the original plan, at Fleury-devant-Douaumont and Fort Souville, driving a salient into the French defences. Fleury was captured and the Germans came within 2.5 mi (4 km) of the Verdun citadel but in July the offensive was limited to provide troops, artillery and ammunition for the Battle of the Somme, leading to a similar transfer of the French Tenth Army to the Somme front. From 23 June to 17 August, Fleury changed hands sixteen times and a German attack on Fort Souville failed. The offensive was reduced further but to keep French troops away from the Somme, ruses were used to disguise the change.

In September and December, French counter-offensives recaptured much ground on the east bank and recovered Fort Douaumont and Fort Vaux. The battle lasted for 302 days, one of the longest and costliest in human history. In 2000, Hannes Heer and Klaus Naumann calculated that the French suffered 377,231 casualties and the Germans 337,000, a total of 714,231 and an average of 70,000 a month. In 2014, William Philpott wrote of 714,000 casualties suffered by both sides during the Battle of Verdun in 1916 and that about 1,250,000 casualties were suffered in the vicinity of Verdun in the war. In France, the battle came to symbolise the determination of the French Army and the destructiveness of the war.

After the German invasion of France had been halted at the First Battle of the Marne in September 1914, the war of movement ended at the Battle of the Yser and the First Battle of Ypres. The Germans built field fortifications to hold the ground captured in 1914 and the French began siege warfare to break through the German defences and recover the lost territory. In late 1914 and in 1915, offensives on the Western Front had failed to gain much ground and been extremely costly in casualties. According to his memoirs written after the war, the Chief of the German General Staff, Erich von Falkenhayn, believed that although victory might no longer be achieved by a decisive battle, the French army could still be defeated if it suffered a sufficient number of casualties. Falkenhayn offered five corps from the strategic reserve for an offensive at Verdun at the beginning of February 1916 but only for an attack on the east bank of the Meuse. Falkenhayn considered it unlikely the French would be complacent about Verdun; he thought that they might send all their reserves there and begin a counter-offensive elsewhere or fight to hold Verdun while the British launched a relief offensive. After the war, Kaiser Wilhelm II and Gerhard Tappen, the Operations Officer at Oberste Heeresleitung (OHL, General Headquarters), wrote that Falkenhayn believed the last possibility was most likely.

By seizing or threatening to capture Verdun, the Germans anticipated that the French would send all their reserves, which would then have to attack secure German defensive positions supported by a powerful artillery reserve. In the Gorlice–Tarnów Offensive (1 May to 19 September 1915), the German and Austro-Hungarian Armies attacked Russian defences frontally, after pulverising them with large amounts of heavy artillery. During the Second Battle of Champagne (Herbstschlacht [autumn battle]) 25 September to 6 November 1915, the French suffered "extraordinary casualties" from the German heavy artillery, which Falkenhayn considered offered a way out of the dilemma of material inferiority and the growing strength of the Allies. In the north, a British relief offensive would wear down British reserves, to no decisive effect but create the conditions for a German counter-offensive near Arras.

Hints about Falkenhayn's thinking were picked up by Dutch military intelligence and passed on to the British in December. The German strategy was to create a favourable operational situation without a mass attack, which had been costly and ineffective when tried by the Franco-British, Falkenhayn intended to rely on the power of heavy artillery to inflict mass casualties. A limited offensive at Verdun would lead to the destruction of the French strategic reserve in fruitless counter-attacks and the defeat of British reserves during a hopeless relief offensive, leading to the French accepting a separate peace. If the French refused to negotiate, the second phase of the strategy would follow, in which the German armies would attack terminally weakened Franco-British armies, mop up the remains of the French armies and expel the British from Europe. To fulfil this strategy, Falkenhayn needed to hold back enough of the strategic reserve to defeat the Anglo-French relief offensives and then conduct a counter-offensive, which limited the number of divisions which could be sent to the 5th Army at Verdun for Unternehmen Gericht (Operation Judgement).

The Fortified Region of Verdun (RFV) lay in a salient formed during the German invasion of 1914. General Joseph Joffre, the Commander-in-Chief of the French Army, had concluded from the swift capture of the Belgian fortresses at the Battle of Liège and at the Siege of Namur in 1914 that fortifications had been made obsolete by German super-heavy siege artillery. In a directive of the General Staff of 5 August 1915, the RFV was to be stripped of 54 artillery batteries and 128,000 rounds of ammunition. Plans to demolish forts Douaumont and Vaux to deny them to the Germans were made and 11,000 lb (5,000 kg) of explosives had been placed in Douaumont by the time of the German offensive on 21 February. The 18 large forts and other batteries around Verdun were left with fewer than 300 guns and a small reserve of ammunition, while their garrisons had been reduced to small maintenance crews. The railway line from the south into Verdun had been cut during the Battle of Flirey in 1914, with the loss of Saint-Mihiel; the line west from Verdun to Paris was cut at Aubréville in mid-July 1915 by the German 3rd Army, which had attacked southwards through the Argonne Forest since the new year.

For centuries, Verdun, on the Meuse river, had played an important role in the defence of the French hinterland. Attila the Hun failed to seize the town in the fifth century and when the empire of Charlemagne was divided under the Treaty of Verdun (843), the town became part of the Holy Roman Empire; the Peace of Westphalia of 1648 awarded Verdun to France. At the heart of the city was a citadel built by Vauban in the 17th century. A double ring of 28 forts and smaller works (ouvrages) had been built around Verdun on commanding ground, at least 490 ft (150 m) above the river valley, 1.6–5.0 mi (2.5–8 km) from the citadel. A programme had been devised by Séré de Rivières in the 1870s to build two lines of fortresses from Belfort to Épinal and from Verdun to Toul as defensive screens and to enclose towns intended to be the bases for counter-attacks.

Many of the Verdun forts had been modernised and made more resistant to artillery, with a reconstruction programme begun at Douaumont in the 1880s. A sand cushion and thick, steel-reinforced concrete tops up to 8 ft 2 in (2.5 m) thick, buried under 3 ft 3 in – 13 ft 1 in (1–4 m) of earth, were added. The forts and ouvrages were sited to overlook each other for mutual support and the outer ring had a circumference of 28 mi (45 km). The outer forts had 79 guns in shellproof turrets and more than 200 light guns and machine-guns to protect the ditches around the forts. Six forts had 155 mm guns in retractable turrets and fourteen had retractable twin 75 mm turrets.

In 1903, Douaumont was equipped with a new concrete bunker (Casemate de Bourges), containing two 75 mm field guns to cover the south-western approach and the defensive works along the ridge to Ouvrage de Froideterre. More guns were added from 1903 to 1913 in four retractable steel turrets. The guns could rotate for all-round defence and two smaller versions, at the north-eastern and north-western corners of the fort, housed twin Hotchkiss machine-guns. On the east side of the fort, an armoured turret with a 155 mm short-barrelled gun faced north and north-east and another housed twin 75 mm guns at the north end, to cover the intervals between the neighbouring forts. The fort at Douaumont formed part of a complex of the village, fort, six ouvrages, five shelters, six concrete batteries, an underground infantry shelter, two ammunition depots and several concrete infantry trenches. The Verdun forts had a network of concrete infantry shelters, armoured observation posts, batteries, concrete trenches, command posts and underground shelters between the forts. The artillery comprised c. 1,000 guns, with 250 in reserve; the forts and ouvrages were linked by telephone and telegraph, a narrow-gauge railway system and a road network; on mobilisation, the RFV had a garrison of 66,000 men and rations for six months.

Verdun had been isolated on three sides since 1914 and the mainline Paris–St Menehould–Les Islettes–Clermont-en-Argonne–Aubréville–Verdun railway in the Forest of Argonne was closed in mid-July 1915, by the right flank divisions of the 5th Army (Generalmajor Crown Prince Wilhelm) when it reached the La Morte Fille–Hill 285 ridge, after continuous local attacks, rendering the railway unusable. Only a light railway remained to the French to carry bulk supplies; German-controlled mainline railways lay only 15 mi (24 km) to the north of the front line. A corps was moved to the 5th Army to provide labour for the preparation of the offensive. Areas were emptied of French civilians and buildings requisitioned. Thousands of kilometres of telephone cable were laid, a huge amount of ammunition and rations was dumped under cover and hundreds of guns were emplaced and camouflaged. Ten new rail lines with twenty stations were built and vast underground shelters (Stollen) 15–46 ft (4.5–14 m) deep were dug, each to accommodate up to 1,200 infantry.

The III Corps, VII Reserve Corps and XVIII Corps were transferred to the 5th Army, each corps being reinforced by 2,400 experienced troops and 2,000 trained recruits. V Corps was placed behind the front line, ready to advance if necessary when the assault divisions were moving up. XV Corps, with two divisions, was in 5th Army reserve, ready to advance and mop up as soon as the French defence collapsed. Special arrangements were made to maintain a high rate of artillery-fire during the offensive; 33+1⁄2 munitions trains per day were to deliver ammunition sufficient for 2,000,000 rounds to be fired in the first six days and another 2,000,000 shells in the next twelve. Five repair shops were built close to the front to reduce delays for maintenance and factories in Germany were made ready, rapidly to refurbish artillery needing more extensive repairs. A redeployment plan for the artillery was devised, to move field guns and mobile heavy artillery forward, under the covering fire of mortars and the super-heavy artillery. A total of 1,201 guns were massed on the Verdun front, two thirds of which were heavy- and super-heavy artillery, which was obtained by stripping modern German artillery from the rest of the Western Front and substituting for it older types and captured Russian and Belgian guns. The German artillery could fire into the Verdun salient from three directions yet remain dispersed around the edges.

The 5th Army divided the attack front into areas, A occupied by the VII Reserve Corps, B by the XVIII Corps, C by the III Corps and D on the Woëvre plain by the XV Corps. The preliminary artillery bombardment was to begin in the morning of 12 February. At 5:00 p.m., the infantry in areas A to C would advance in open order, supported by grenade and flame-thrower detachments. Wherever possible, the French advanced trenches were to be occupied and the second position reconnoitred for the artillery to bombard on the second day. Great emphasis was placed on limiting German infantry casualties by sending them to follow up destructive bombardments by the artillery, which was to carry the burden of the offensive in a series of large "attacks with limited objectives", to maintain a relentless pressure on the French. The initial objectives were the Meuse Heights, on a line from Froide Terre to Fort Souville and Fort Tavannes, which would provide a secure defensive position from which to repel French counter-attacks. "Relentless pressure" was a term added by the 5th Army staff and created ambiguity about the purpose of the offensive. Falkenhayn wanted land to be captured from which artillery could dominate the battlefield and the 5th Army wanted a quick capture of Verdun. The confusion caused by the ambiguity was left to the corps headquarters to sort out.

Control of the artillery was centralised by an Order for the Activities of the Artillery and Mortars, which stipulated that the corps Generals of Foot Artillery were responsible for local target selection, while co-ordination of flanking fire by neighbouring corps and the fire of certain batteries, was reserved to the 5th Army headquarters. French fortifications were to be engaged by the heaviest howitzers and enfilade fire. The heavy artillery was to maintain long-range bombardment of French supply routes and assembly areas; counter-battery fire was reserved for specialist batteries firing gas shells. Co-operation between the artillery and infantry was stressed, with accuracy of the artillery being given priority over rate of fire. The opening bombardment was to build up slowly and Trommelfeuer (a rate of fire so rapid that the sound of shell-explosions merged into a rumble) would not begin until the last hour. As the infantry advanced, the artillery would increase the range of the bombardment to destroy the French second position. Artillery observers were to advance with the infantry and communicate with the guns by field telephones, flares and coloured balloons. When the offensive began, the French were to be bombarded continuously, with harassing fire being maintained at night.

In 1915, 237 guns and 647 long tons (657 t) of ammunition in the forts of the RFV had been removed, leaving only the heavy guns in retractable turrets. The conversion of the RFV to a conventional linear defence, with trenches and barbed wire began but proceeded slowly, after resources were sent west from Verdun for the Second Battle of Champagne (25 September to 6 November 1915). In October 1915, building began on trench lines known as the first, second and third positions and in January 1916, an inspection by General Noël de Castelnau, Chief of Staff at French General Headquarters (GQG), reported that the new defences were satisfactory, except for small deficiencies in three areas. The fortress garrisons had been reduced to small maintenance crews and some of the forts had been readied for demolition. The maintenance garrisons were responsible to the central military bureaucracy in Paris and when the XXX Corps commander, Major-General Paul Chrétien, attempted to inspect Fort Douaumont in January 1916, he was refused entry.

Douaumont was the largest fort in the RFV and by February 1916, the only artillery left in the fort were the 75 mm and 155 mm turret guns and light guns covering the ditch. The fort was used as a barracks by 68 technicians under the command of Warrant Officer Chenot, the Gardien de Batterie. One of the rotating 6.1 in (155 mm) turrets was partially manned and the other was left empty. The Hotchkiss machine-guns were stored in boxes and four 75 mm guns in the casemates had already been removed. The drawbridge had been jammed in the down position by a German shell and had not been repaired. The coffres (wall bunkers) with Hotchkiss revolver-cannons protecting the moats, were unmanned and over 11,000 lb; 4.9 long tons (5,000 kg) of explosives had been placed in the fort to demolish it. Colonel Émile Driant was stationed at Verdun and criticised Joffre for removing the artillery guns and infantry from fortresses around Verdun. Joffre did not listen but Colonel Driant received the support of the Minister for War Joseph Gallieni. The formidable Verdun defences were a shell and were now threatened by a German offensive; Driant was to be proved correct by events.

In late January 1916, French intelligence obtained an accurate assessment of German military capacity and intentions at Verdun but Joffre considered that an attack would be a diversion, because of the lack of an obvious strategic objective. By the time of the German offensive, Joffre expected a bigger attack elsewhere but finally yielded to political pressure and ordered the VII Corps to Verdun on 23 January, to hold the north face of the west bank. XXX Corps held the salient east of the Meuse to the north and north-east and II Corps held the eastern face of the Meuse Heights; Herr had 8+1⁄2 divisions in the front line, with 2+1⁄2 divisions in close reserve. Groupe d'armées du centre (GAC, General De Langle de Cary) had the I and XX corps with two divisions each in reserve, plus most of the 19th Division; Joffre had 25 divisions in the French strategic reserve. French artillery reinforcements had brought the total at Verdun to 388 field guns and 244 heavy guns, against 1,201 German guns, two thirds of which were heavy and super heavy, including 14 in (360 mm) and 202 mortars, some being 16 in (410 mm). Eight specialist flame-thrower companies were also sent to the 5th Army.

Castelnau met De Langle de Cary on 25 February, who doubted the east bank could be held. Castelnau disagreed and ordered General Frédéric-Georges Herr the corps commander, to hold the right (east) bank of the Meuse at all costs. Herr sent a division from the west bank and ordered XXX Corps to hold a line from Bras to Douaumont, Vaux and Eix. Pétain took over command of the defence of the RFV at 11:00 p.m., with Colonel Maurice de Barescut as chief of staff and Colonel Bernard Serrigny as head of operations, only to hear that Fort Douaumont had fallen. Pétain ordered the remaining Verdun forts to be re-garrisoned.

Four groups were established, under the command of Generals Adolphe Guillaumat, Balfourier and Denis Duchêne on the right bank and Georges de Bazelaire on the left bank. A "line of resistance" was established on the east bank from Souville to Thiaumont, around Fort Douaumont to Fort Vaux, Moulainville and along the ridge of the Woëvre. On the west bank, the line ran from Cumières to Mort Homme, Côte 304 and Avocourt. A "line of panic" was planned in secret as a final line of defence north of Verdun, through forts Belleville, St Michel and Moulainville. I Corps and XX Corps arrived from 24 to 26 February, increasing the number of divisions in the RFV to 14+1⁄2. By 6 March, the arrival of the XIII, XXI, XIV and XXXIII corps had increased the total to 20+1⁄2 divisions.

Unternehmen Gericht (Operation Judgement) was due to begin on 12 February but fog, heavy rain and high winds delayed the offensive until 7:15 a.m. on 21 February, when a 10-hour artillery bombardment by 808 guns began. The German artillery fired c. 1,000,000 shells along a front about 19 mi (30 km) long by 3.1 mi (5 km) wide. The main concentration of fire was on the right (east) bank of the Meuse river. Twenty-six super-heavy, long-range guns, up to 17-inch (420 mm), fired on the forts and the city of Verdun; a rumble that could be heard 99 mi (160 km) away.

The bombardment was paused at midday as a ruse to prompt French survivors to reveal themselves and German artillery-observation aircraft were able to fly over the battlefield unchallenged. The III Corps, VII Corps and XVIII Corps attacked at 4:00 p.m.; the Germans used flamethrowers and stormtroopers followed closely with rifles slung, using hand grenades to kill the remaining defenders. This tactic had been developed by Captain Willy Rohr and Sturm-Bataillon Nr. 5 (Rohr) which delivered the attack. French survivors engaged the attackers, yet the Germans suffered only c. 600 casualties.

By 22 February, German troops had advanced 3.1 mi (5 km) and captured Bois des Caures at the edge of the village of Flabas. Two French battalions had held the bois (wood) for two days but were forced back to Samogneux, Beaumont-en-Auge and Ornes. Driant was killed, fighting with the 56th and 59th Bataillons de chasseurs à pied and only 118 of the Chasseurs managed to escape. Poor communications meant that only then did the French High Command realise the seriousness of the attack. The Germans managed to take the village of Haumont but French forces repulsed a German attack on the village of Bois de l'Herbebois. On 23 February, a French counter-attack at Bois des Caures was defeated.

Fighting for Bois de l'Herbebois continued until the Germans outflanked the French defenders from Bois de Wavrille. The German attackers suffered many casualties during their attack on Bois de Fosses and the French held on to Samogneux. German attacks continued on 24 February and the French XXX Corps was forced out of the second line of defence; XX Corps (General Maurice Balfourier) arrived at the last minute and was rushed forward. That evening Castelnau advised Joffre that the Second Army, under General Pétain, should be sent to the RFV. The Germans had captured Beaumont-en-Verdunois, Bois des Fosses and Bois des Caurières and were moving up ravin Hassoule, which led to Fort Douaumont.

At 3:00 p.m. on 25 February, infantry of Brandenburg Regiment 24 advanced with the II and III battalions side-by-side, each formed into two waves composed of two companies each. A delay in the arrival of orders to the regiments on the flanks, led to the III Battalion advancing without support on that flank. The Germans rushed French positions in the woods and on Côte 347, with the support of machine-gun fire from the edge of Bois Hermitage. The German infantry took many prisoners as the French on Côte 347 were outflanked and withdrew to Douaumont village. The German infantry had reached their objectives in under twenty minutes and pursued the French, until fired on by a machine-gun in Douaumont church. Some German troops took cover in woods and a ravine which led to the fort, when German artillery began to bombard the area, the gunners having refused to believe claims sent by field telephone that the German infantry were within a few hundred metres of the fort. Several German parties were forced to advance to find cover from the German shelling and two parties independently made for the fort. The Germans did not know that the French garrison was made up of only a small maintenance crew led by a warrant officer, since most of the Verdun forts had been partly disarmed, after the demolition of Belgian forts in 1914, by the German super-heavy Krupp 420 mm mortars.

The German party of c. 100 soldiers tried to signal to the artillery with flares but they were not seen due to the twilight and falling snow. Some of the party began to cut through the wire around the fort, while French machine-gun fire from Douaumont village ceased. The French had seen the German flares and took the Germans on the fort to be Zouaves retreating from Côte 378. The Germans were able to reach the north-east end of the fort before the French resumed firing. The German party found a way through the railings on top of the ditch and climbed down without being fired on, since the machine-gun bunkers (coffres de contrescarpe) at each corner of the ditch had been left unmanned. The German parties continued and found a way inside the fort through one of the unoccupied ditch bunkers and then reached the central Rue de Rempart.

After quietly moving inside, the Germans heard voices and persuaded a French prisoner, captured in an observation post, to lead them to the lower floor, where they found Warrant Officer Chenot and about 25 French troops, most of the skeleton garrison of the fort, and took them prisoner. On 26 February, the Germans had advanced 1.9 mi (3 km) on a 6.2 mi (10 km) front; French losses were 24,000 men and German losses were c. 25,000 men. A French counter-attack on Fort Douaumont failed and Pétain ordered that no more attempts were to be made; existing lines were to be consolidated and other forts were to be occupied, rearmed and supplied to withstand a siege if surrounded.

The German advance gained little ground on 27 February, after a thaw turned the ground into a swamp and the arrival of French reinforcements increased the effectiveness of the defence. Some German artillery became unserviceable and other batteries became stranded in the mud. German infantry began to suffer from exhaustion and unexpectedly high losses, 500 casualties being suffered in the fighting around Douaumont village. On 29 February, the German advance was contained at Douaumont by a heavy snowfall and the defence of French 33rd Infantry Regiment. Delays gave the French time to bring up 90,000 men and 23,000 short tons (21,000 t) of ammunition from the railhead at Bar-le-Duc to Verdun. The swift German advance had gone beyond the range of artillery covering fire and the muddy conditions made it very difficult to move the artillery forward as planned. The German advance southwards brought it into range of French artillery west of the Meuse, whose fire caused more German infantry casualties than in the earlier fighting, when French infantry on the east bank had fewer guns in support.

Before the offensive, Falkenhayn had expected that French artillery on the west bank would be suppressed by counter-battery fire but this had failed. The Germans set up a specialist artillery force to counter French artillery fire from the west bank but this also failed to reduce German infantry casualties. The 5th Army asked for more troops in late February but Falkenhayn refused, due to the rapid advance already achieved on the east bank and because he needed the rest of the OHL reserve for an offensive elsewhere, once the attack at Verdun had attracted and consumed French reserves. The pause in the German advance on 27 February led Falkenhayn to have second thoughts to decide between terminating the offensive or reinforcing it. On 29 February, Knobelsdorf, the 5th Army Chief of Staff, prised two divisions from the OHL reserve, with the assurance that once the heights on the west bank had been occupied, the offensive on the east bank could be completed. The VI Reserve Corps was reinforced with the X Reserve Corps, to capture a line from the south of Avocourt to Côte 304 north of Esnes, Le Mort Homme, Bois des Cumières and Côte 205, from which the French artillery on the west bank could be destroyed.

The artillery of the two-corps assault group on the west bank was reinforced by 25 heavy artillery batteries, artillery command was centralised under one officer and arrangements were made for the artillery on the east bank to fire in support. The attack was planned by General Heinrich von Gossler in two parts, on Mort-Homme and Côte 265 on 6 March, followed by attacks on Avocourt and Côte 304 on 9 March. The German bombardment reduced the top of Côte 304 from a height of 997 ft (304 m) to 980 ft (300 m); Mort-Homme sheltered batteries of French field guns, which hindered German progress towards Verdun on the right bank; the hills also provided commanding views of the left bank. After storming the Bois des Corbeaux and then losing it to a French counter-attack, the Germans launched another assault on Mort-Homme on 9 March, from the direction of Béthincourt to the north-west. Bois des Corbeaux was captured again at great cost in casualties, before the Germans took parts of Mort-Homme, Côte 304, Cumières and Chattancourt on 14 March.

After a week, the German attack had reached the first-day objectives, to find that French guns behind Côte de Marre and Bois Bourrus were still operational and inflicting many casualties among the Germans on the east bank. German artillery moved to Côte 265, was subjected to systematic artillery fire by the French, which left the Germans needing to implement the second part of the west bank offensive, to protect the gains of the first phase. German attacks changed from large operations on broad fronts, to narrow-front attacks with limited objectives.

On 14 March a German attack captured Côte 265 at the west end of Mort-Homme but the French 75th Infantry Brigade managed to hold Côte 295 at the east end. On 20 March, after a bombardment by 13,000 trench mortar rounds, the 11th Bavarian and 11th Reserve divisions attacked Bois d'Avocourt and Bois de Malancourt and reached their initial objectives easily. Gossler ordered a pause in the attack, to consolidate the captured ground and to prepare another big bombardment for the next day. On 22 March, two divisions attacked "Termite Hill" near Côte 304 but were met by a mass of artillery fire, which also fell on assembly points and the German lines of communication, ending the German advance.

The limited German success had been costly and French artillery inflicted more casualties as the German infantry tried to dig in. By 30 March, Gossler had captured Bois de Malancourt at a cost of 20,000 casualties and the Germans were still short of Côte 304. On 30 March, the XXII Reserve Corps arrived as reinforcements and General Max von Gallwitz took command of a new Attack Group West (Angriffsgruppe West). Malancourt village was captured on 31 March, Haucourt fell on 5 April and Béthincourt on 8 April. On the east bank, German attacks near Vaux reached Bois Caillette and the Vaux–Fleury railway but were then driven back by the French 5th Division. An attack was made on a wider front along both banks by the Germans at noon on 9 April, with five divisions on the left bank but this was repulsed except at Mort-Homme, where the French 42nd Division was forced back from the north-east face. On the right bank an attack on Côte-du-Poivre failed.

In March the German attacks had no advantage of surprise and faced a determined and well-supplied adversary in superior defensive positions. German artillery could still devastate the French positions but could not prevent French artillery fire from inflicting many casualties on German infantry and isolating them from their supplies. Massed artillery fire could enable German infantry to make small advances but massed French artillery fire could do the same for French infantry when they counter-attacked, which often repulsed the German infantry and subjected them to constant losses, even when captured ground was held. The German effort on the west bank also showed that capturing a vital point was not sufficient, because it would be found to be overlooked by another terrain feature, which had to be captured to ensure the defence of the original point, which made it impossible for the Germans to terminate their attacks, unless they were willing to retire to the original front line of February 1916.

By the end of March the offensive had cost the Germans 81,607 casualties and Falkenhayn began to think of ending the offensive, lest it become another costly and indecisive engagement similar to the First Battle of Ypres in late 1914. The 5th Army staff requested more reinforcements from Falkenhayn on 31 March with an optimistic report claiming that the French were close to exhaustion and incapable of a big offensive. The 5th Army command wanted to continue the east bank offensive until a line from Ouvrage de Thiaumont, to Fleury, Fort Souville and Fort de Tavannes had been reached, while on the west bank the French would be destroyed by their own counter-attacks. On 4 April, Falkenhayn replied that the French had retained a considerable reserve and that German resources were limited and not sufficient to replace continuously men and munitions. If the resumed offensive on the east bank failed to reach the Meuse Heights, Falkenhayn was willing to accept that the offensive had failed and end it.

The failure of German attacks in early April by Angriffsgruppe Ost, led Knobelsdorf to take soundings from the 5th Army corps commanders, who unanimously wanted to continue. The German infantry were exposed to continuous artillery fire from the flanks and rear; communications from the rear and reserve positions were equally vulnerable, which caused a constant drain of casualties. Defensive positions were difficult to build, because existing positions were on ground which had been swept clear by German bombardments early in the offensive, leaving German infantry with very little cover. General Berthold von Deimling, commander of XV Corps, also wrote that French heavy artillery and gas bombardments were undermining the morale of the German infantry, which made it necessary to keep going to reach safer defensive positions. Knobelsdorf reported these findings to Falkenhayn on 20 April, adding that if the Germans did not go forward, they must go back to the start line of 21 February.

Knobelsdorf rejected the policy of limited piecemeal attacks tried by Mudra as commander of Angriffsgruppe Ost and advocated a return to wide-front attacks with unlimited objectives, swiftly to reach the line from Ouvrage de Thiaumont to Fleury, Fort Souville and Fort de Tavannes. Falkenhayn was persuaded to agree to the change and by the end of April, 21 divisions, most of the OHL reserve, had been sent to Verdun and troops had also been transferred from the Eastern Front. The resort to large, unlimited attacks was costly for both sides but the German advance proceeded only slowly. Rather than causing devastating French casualties by heavy artillery with the infantry in secure defensive positions, which the French were compelled to attack, the Germans inflicted casualties by attacks which provoked French counter-attacks and assumed that the process inflicted five French casualties for two German losses.

In mid-March, Falkenhayn had reminded the 5th Army to use tactics intended to conserve infantry, after the corps commanders had been allowed discretion to choose between the cautious, "step by step" tactics desired by Falkenhayn and maximum efforts, intended to obtain quick results. On the third day of the offensive, the 6th Division of the III Corps (General Ewald von Lochow), had ordered that Herbebois be taken regardless of loss and the 5th Division had attacked Wavrille to the accompaniment of its band. Falkenhayn urged the 5th Army to use Stoßtruppen (storm units) composed of two infantry squads and one of engineers, armed with automatic weapons, hand grenades, trench mortars and flame-throwers, to advance in front of the main infantry body. The Stoßtruppen would conceal their advance by shrewd use of terrain and capture any blockhouses which remained after the artillery preparation. Strongpoints which could not be taken were to be by-passed and captured by follow-up troops. Falkenhayn ordered that the command of field and heavy artillery units was to be combined, with a commander at each corps headquarters. Common observers and communication systems would ensure that batteries in different places could bring targets under converging fire, which would be allotted systematically to support divisions.

In mid-April, Falkenhayn ordered that infantry should advance close to the barrage, to exploit the neutralising effect of the shellfire on surviving defenders, because fresh troops at Verdun had not been trained in these methods. Knobelsdorf persisted with attempts to maintain momentum, which was incompatible with casualty conservation by limited attacks, with pauses to consolidate and prepare. Mudra and other commanders who disagreed were sacked. Falkenhayn also intervened to change German defensive tactics, advocating a dispersed defence with the second line to be held as a main line of resistance and jumping-off point for counter-attacks. Machine-guns were to be set up with overlapping fields of fire and infantry given specific areas to defend. When French infantry attacked, they were to be isolated by Sperrfeuer (barrage-fire) on their former front line, to increase French infantry casualties. The changes desired by Falkenhayn had little effect, because the main cause of German casualties was artillery fire, just as it was for the French.

From 10 May German operations were limited to local attacks, either in reply to French counter-attacks on 11 April between Douaumont and Vaux and on 17 April between the Meuse and Douaumont, or local attempts to take points of tactical value. At the beginning of May, General Pétain was promoted to the command of Groupe d'armées du centre (GAC) and General Robert Nivelle took over the Second Army at Verdun. From 4 to 24 May, German attacks were made on the west bank around Mort-Homme and on 4 May, the north slope of Côte 304 was captured; French counter-attacks from 5 to 6 May were repulsed. The French defenders on the crest of Côte 304 were forced back on 7 May but German infantry were unable to occupy the ridge, because of the intensity of French artillery fire. Cumieres and Caurettes fell on 24 May as a French counter-attack began at Fort Douaumont.

In May, General Nivelle, who had taken over the Second Army, ordered General Charles Mangin, commander of the 5th Division to plan a counter-attack on Fort Douaumont. The initial plan was for an attack on a 1.9 mi (3 km) front but several minor German attacks captured the Fausse-Côte and Couleuvre ravines on the south-east and west sides of the fort. A further attack took the ridge south of the ravin de Couleuvre, which gave the Germans better routes for counter-attacks and observation over the French lines to the south and south-west. Mangin proposed a preliminary attack to retake the area of the ravines, to obstruct the routes by which a German counter-attack on the fort could be made. More divisions were necessary but these were refused to preserve the troops needed for the forthcoming offensive on the Somme; Mangin was limited to one division for the attack with one in reserve. Nivelle reduced the attack to an assault on Morchée Trench, Bonnet-d'Evèque, Fontaine Trench, Fort Douaumont, a machine-gun turret and Hongrois Trench, which would require an advance of 550 yd (500 m) on a 1,260 yd (1,150 m) front.

III Corps was to command the attack by the 5th Division and the 71st Brigade, with support from three balloon companies for artillery observation and a fighter group. The main effort was to be conducted by two battalions of the 129th Infantry Regiment, each with a pioneer company and a machine-gun company attached. The 2nd Battalion was to attack from the south and the 1st Battalion was to move along the west side of the fort to the north end, taking Fontaine Trench and linking with the 6th Company. Two battalions of the 74th Infantry Regiment were to advance along the east and south-east sides of the fort and take a machine-gun turret on a ridge to the east. Flank support was arranged with neighbouring regiments and diversions were planned near Fort Vaux and the ravin de Dame. Preparations for the attack included the digging of 7.5 mi (12 km) of trenches and the building of large numbers of depots and stores but little progress was made due to a shortage of pioneers. French troops captured on 13 May, disclosed the plan to the Germans, who responded by subjecting the area to more artillery harassing fire, which also slowed French preparations.

The French preliminary bombardment by four 370 mm mortars and 300 heavy guns, began on 17 May and by 21 May, the French artillery commander claimed that the fort had been severely damaged. During the bombardment the German garrison in the fort experienced great strain, as French heavy shells smashed holes in the walls and concrete dust, exhaust fumes from an electricity generator and gas from disinterred corpses polluted the air. Water ran short but until 20 May, the fort remained operational, reports being passed back and reinforcements moving forward until the afternoon, when the Bourges Casemate was isolated and the wireless station in the north-western machine-gun turret burnt down.

Conditions for the German infantry in the vicinity were far worse and by 18 May, the French destructive bombardment had obliterated many defensive positions, the survivors sheltering in shell-holes and dips of the ground. Communication with the rear was severed and food and water ran out by the time of the French attack on 22 May. The troops of Infantry Regiment 52 in front of Fort Douaumont had been reduced to 37 men near Thiaumont Farm and German counter-barrages inflicted similar losses on French troops. On 22 May, French Nieuport fighters attacked eight observation balloons and shot down six for the loss of one Nieuport 16; other French aircraft attacked the 5th Army headquarters at Stenay. German artillery fire increased and twenty minutes before zero hour, a German bombardment began, which reduced the 129th Infantry Regiment companies to about 45 men each.

The assault began at 11:50 a. m. on 22 May on a 0.62 mi (1 km) front. On the left flank the 36th Infantry Regiment attack quickly captured Morchée Trench and Bonnet-d'Evèque but suffered many casualties and the regiment could advance no further. The flank guard on the right was pinned down, except for one company which disappeared and in Bois Caillette, a battalion of the 74th Infantry Regiment was unable to leave its trenches; the other battalion managed to reach its objectives at an ammunition depot, shelter DV1 at the edge of Bois Caillette and the machine-gun turret east of the fort, where the battalion found its flanks unsupported.

Despite German small-arms fire, the 129th Infantry Regiment reached the fort in a few minutes and managed to get in through the west and south sides. By nightfall, about half of the fort had been recaptured and next day, the 34th Division was sent to reinforce the French troops in the fort. The attempt to reinforce the fort failed and German reserves managed to cut off the French troops inside and force them to surrender, 1,000 French prisoners being taken. After three days, the French had suffered 5,640 casualties from the 12,000 men in the attack and the Germans suffered 4,500 casualties in Infantry Regiment 52, Grenadier Regiment 12 and Leib-Grenadier Regiment 8 of the 5th Division.