The Stalemate of Attrition

By the summer of 1916, the Battle of Verdun had become the quintessential representation of World War I’s brutal stalemate. What began as Germany’s strategic operation to “bleed France white” had devolved into a grueling ten-month struggle that would claim over 700,000 casualties. The battlefield, once picturesque French countryside, had been transformed into a nightmarish landscape of shell craters, shattered forests, and makeshift graves. Both armies were exhausted, yet neither could afford to retreat from what had become a symbolic struggle for national honor. The French commander Philippe Pétain’s famous declaration “Ils ne passeront pas!” had become a rallying cry, but the reality was that French forces were stretched to their breaking point, holding onto defensive positions through sheer determination and increasingly desperate tactics.

The Strategic Importance of Fort Souville

The entire Verdun defensive system relied on a series of ridges extending laterally toward the Meuse River, with Fort Souville commanding the final major ridge line. Behind it lay only the Belleville Ridge, where two second-rate forts were expected to crumble against any significant assault. From Fort Souville to Verdun itself stretched a mere 2.5-mile downhill slope—making the fort the linchpin of Pétain’s originally conceived “last line of defense.” Its fall would inevitably lead to the capture of Verdun. The approach to Fort Souville ran along a ridge connecting two main transverse ridges, resembling the crossbar of the letter H. This critical terrain feature was controlled at its far end by the Thiaumont works—fiercely contested and currently in French hands—while the village of Fleury dominated its center. Any assault on Fort Souville would require capturing both positions first.

Germany’s Renewed Offensive Preparations

General von Knobelsdorf, commanding the German Fifth Army, assembled 30,000 soldiers for what he envisioned as the final breakthrough operation. Among them was General Krafft von Dellmensingen’s renowned mountain corps, freshly arrived at the front with an impressive reputation within the German army. The attack front measured approximately three miles, resulting in troop concentrations even denser than those during the initial February offensive. Despite the diversion of resources to counter the Russian Brusilov Offensive on the Eastern Front, von Knobelsdorf remained remarkably optimistic, predicting his forces would reach Verdun within three days. His confidence manifested in tangible preparations: he summoned regimental colors and military bands for a victory parade through the captured city and extended an invitation to Emperor Wilhelm II to witness what he believed would be the decisive blow from Fifth Army headquarters. Even Colonel Bansi, commander of the heavy artillery, captured the mood in his diary, writing enthusiastically about riding between artillery batteries “through sunlit meadows full of wildflowers… it gives one courage and confidence, refreshing and renewing the spirit.”

The Secret Weapon: Green Cross Shells

As German assault troops moved toward their jump-off positions, they passed artillery emplacements stocked with shell casings marked with bright green crosses. This unfamiliar symbol created an aura of mystery, yet many soldiers interpreted it as evidence of their commanders’ assurance that this time would be different—this time they would break through to Verdun. The marked shells contained a new chemical weapon that German scientists had spent months developing: a toxic gas specifically designed to penetrate French gas masks. This represented a significant evolution in chemical warfare, which had begun with simple chlorine gas attacks at Ypres in 1915 and had since progressed through various deadly formulations. The German High Command believed this new agent would overcome the defensive measures that had gradually neutralized previous gas attacks.

The Eerie Silence of June 22

On the evening of June 22, 1916, Lieutenant Marcel Bechu of the French 130th Division was about to dine with his commanding general at their headquarters near Fort Souville. It was a windless summer evening, with only the constant rumble of German artillery disturbing the peace. Suddenly, the German bombardment ceased. For the first time in days, complete silence descended upon the battlefield—a silence that, as Bechu noted, “seemed more terrible than the thunder of cannons.” Officers exchanged suspicious glances, fearing some unknown trap. French artillery continued firing, but received no response from German guns. The strange quiet persisted for several minutes that felt like hours, creating growing unease in the French shelters. Then came a new sound overhead, which Bechu poetically described as “countless soft whistles, continuous, as if thousands of birds were simultaneously taking flight, escaping over our heads before being swallowed by the Ravine des Hospices behind us.”

The Death Carnival Begins

A sergeant suddenly burst into the shelter without knocking or salting, his mouth twitching with excitement. “General, shells—thousands of them—flying overhead but not exploding!” The general simply said, “Let’s go see.” Outside, Bechu could hear distant German guns firing, yet still no explosions. Then, from the ravine, rose “a foul, nauseating odor of decaying compounds, with the musty smell of vinegar gone bad.” Someone whispered in a tense voice: “Gas! It’s gas!” Nearby, Lieutenant Pierre de Mazenod of the 129th Division heard the silent shells falling around his 75mm gun battery, thinking it sounded like “thousands of beads falling on a giant carpet.” His soldiers initially rejoiced at what they believed were dud shells, but then the pungent gas reached them, bringing the first sensations of suffocation. Horses harnessed to gun carriages reared in panic, breaking their reins and stampeding among the artillery pieces. Gunners scrambled to don gas masks and man their positions—a scene de Mazenod likened to a “death carnival.”

The Horrific Effectiveness of Green Cross Gas

The primitive gas masks provided only partial protection against the new chemical agent. Soldiers wearing masks still coughed, vomited, and desperately clutched their throats for air. The gas—later identified as a mixture of phosgene and chlorine—penetrated the French masks’ filters more effectively than any previous chemical weapon. Phosgene, particularly deadly because its symptoms often delayed onset for hours, would ultimately claim more lives than any other chemical weapon of World War I. The German bombardment continued through the night, with Green Cross shells accounting for approximately 80,000 of the 110,000 gas shells fired that day. The psychological impact proved as devastating as the physiological effects—the French defenders realized their protective equipment had been rendered nearly obsolete.

The Aftermath and Failed Assault

Following the gas attack, German infantry advanced through the contaminated terrain, expecting to find the French defenses neutralized. While the gas had indeed caused significant casualties and disruption, enough French soldiers survived to mount a desperate resistance. Fighting raged for control of Fleury village and the Thiaumont works, with positions changing hands multiple times. The German assault troops, despite their numerical advantage and preliminary gas attack, found themselves bogged down in the same brutal close-quarters combat that had characterized Verdun for months. Von Knobelsdorf’s promised three-day victory failed to materialize as French reinforcements arrived and counterattacks stabilized the situation. By early July, the German offensive had stalled completely, with Fort Souville remaining in French hands.

Cultural and Social Impacts

The Battle of Verdun, and particularly the June 22 gas attack, left deep scars on the collective psyche of both nations. For the French, the experience reinforced the narrative of heroic resistance against overwhelming odds, but also exposed the horrifying reality of modern technological warfare. The image of gas-masked soldiers continuing to fight while suffocating became emblematic of the entire Verdun experience—a testament to human endurance amid unimaginable suffering. German soldiers, meanwhile, faced the disillusionment of seeing their superior technology and careful planning still fail to achieve breakthrough. The promised victory parade through Verdun never happened, and the emperor never visited the front to witness the triumph that wasn’t. The gap between command expectations and battlefield reality widened further, contributing to growing war-weariness and questioning of military leadership on both sides.

Medical and Technological Legacy

The Green Cross attack represented a significant escalation in chemical warfare that prompted rapid developments in protective equipment and treatment protocols. Medical services on both sides gained valuable experience in treating mass chemical casualties, though adequate treatment for phosgene exposure would remain limited throughout the war. The incident accelerated research into more effective gas masks, leading to improvements that would eventually neutralize Germany’s temporary advantage. More broadly, the event demonstrated the increasingly scientific approach to warfare, where chemists, physicists, and engineers played as important a role as generals in developing new weapons systems. This transformation would continue throughout the 20th century, making technological innovation a central component of military planning.

Verdun’s Enduring Symbolism

The failure of Germany’s final offensive at Verdun marked the beginning of the battle’s final phase. By December 1916, French forces had regained most of the territory lost since February, though at tremendous cost. The battle became synonymous with the futility and horror of trench warfare, influencing military doctrine for decades to come. The specific memory of the June 22 gas attack lived on in veterans’ accounts and regimental histories, serving as a potent example of warfare’s relentless evolution toward more destructive and impersonal methods. Memorials at Verdun today acknowledge the chemical warfare aspects of the battle alongside the more conventional combat, ensuring that this dimension of the suffering is not forgotten.

Modern Relevance and Ethical Considerations

The events at Verdun continue to inform contemporary discussions about the ethics of warfare, particularly regarding chemical weapons. The 1925 Geneva Protocol and subsequent chemical weapons bans drew heavily from the horrific experiences of World War I, including the Green Cross attack at Verdun. Military historians still study the battle for lessons in defensive planning, logistics, and the psychological dimensions of prolonged combat. For the general public, Verdun remains a powerful symbol of both human resilience and the catastrophic costs of nationalist fervor—a reminder that technological superiority alone cannot guarantee victory when met with determined opposition. The silent guns that preceded the gas attack, followed by the suffering that penetrated even protective masks, created a haunting narrative that continues to resonate as we confront new ethical challenges in modern warfare.