Here are the 10 Bloodiest Battles of World War I

The Ninth Bloodiest: The Battle of Galicia

The Battle of Galicia involved Austro-Hungarian forces, with Russian forces on the opposing side, from August 23, 1914 to September 11, 1914. This battle occurred less than a month after the beginning of World War I, and planning for the Battle of Galicia began in the first days of the war. Austria-Hungary declared war on July 28, and Germany followed on August 1; the two countries had not specified the terms of their alliance. Germany intended to direct the majority of its efforts toward the conquest of France, leaving only one army division of eight available to engage with Russia.

Germany requested Austro-Hungarian aid to defeat the Russians in East Prussia and Poland. Austria-Hungary redirected troops intended for Serbia to deal with the Russians in August of 1914. Austria-Hungary was prepared to engage from a base in Galicia on August 20. Austro-Hungarian forces were under the command of Franz Conrad von Hötzendorf. He directed his troops from Galicia into Russia.

The early battles of Krasnik and Komarov were successes for Austria-Hungary; however, they were less successful at the Battle of Gnila Lipa. While the Russians had experienced an early defeat at Krasnik and Komarov, Gnila Lipa changed the overall pathway of the Battle of Galicia. Two Russian armies were already present at Gnila Lipa, and were joined by other army divisions.

The Austro-Hungarian armies retreated across the entire front, leaving Galicia to the Russians. In total, Austria-Hungary had more than 100,000 dead, another 220,000 wounded, and some 100,000 captured. Supplies, rail cars, and a valuable fortress were lost to the Russians. The Russians also experienced significant losses, with around 250,000 wounded or dead and 40,000 captured. Proportionally, however, the losses were much more severe for the Austro-Hungarian military. The Russians were much more able to transport troops and supplies, and to rebuild following their losses.

The Eighth Bloodiest: The Battle of Verdun

The Battle of Verdun was the longest battle of World War I, lasting some 300 days. Verdun involved the armies of France and Germany, and resulted in an eventual French victory, with few actual gains. While Verdun produced few significant gains, it did play a substantial role in shifting the direction of World War I, and engaging the forces of Britain in the Battle of the Somme.

The Germans made the decision to focus their attention on the Western Front quite early in World War I, and continued that plan throughout the war. As part of this plan, the town of Verdun in France was attacked by a large German force on February 21, 1916. Codenamed judgment by the Germans, the offensive against Verdun was a direct attack on the spirit of the French nation. Verdun was a historically significant region, and one that was already heavily fortified. The Germans believed that the French would be willing to devote the full resources of the French military to the defense of Verdun.

The German army, under the command of Erich von Falkenhayn, believed that a victory in Verdun would be relatively rapid. The Germans had significantly more powerful artillery, and expected to inflict significant casualties at a low overall cost. The Germans gained land initially in the February offensive, but over the course of the long battle, lost these gains. This strategy failed and both Germany and France began sending more and more men to the front in Verdun.

The Battle of Verdun was a costly one, and as noted, not a particularly successful one. Both the Germans and the French lacked access to clear and efficient supply lines, and the Germans were lacking a clear strategy for victory. Falkenhayn resigned in August, and the Germans maintained only a defense. By the end of the battle in December, the Germans had lost all of their early gains. In total, some 800,000 soldiers were wounded, killed or missing following the Battle of Verdun.

The Seventh Bloodies: The Second Battle of the Somme

The Germans, under the command of Erich Ludendorff, launched five significant offenses in the spring and summer of 1918. The Second Battle of the Somme was the first of these offenses. In 1918, Russia had pulled out of World War I, and the United States had not yet entered the war. This was a window in which there was a clear opportunity for a German victory; however, history would not see Germany win the war.

The Germans planned to attack a fifty-mile-long front, bordered by the Somme River in the south, and the town of Arras, held by the British, in the north. Eventually, German forces would cross the river. The river would provide a defensible border against French forces early in the Battle. Germany committed significant forces to the offensive. As noted, Arras was held by the British, and British forces were engaged in the Second Battle of the Somme, including the Third Army and Fifth Army. The Fifth Army was significantly stronger than the Third.

Germany devoted a huge number of resources to this battle, including some 6,500 large artillery guns and 3,000 mortars. The battle began at 4:40 in the morning on March 21, 1918, with a massive artillery attack, including explosives, poison gas, and smoke. The British lines sustained substantial casualties and disruptions both in the front and rear of the lines. An infantry assault followed; however, the overall costs were high. The Germans gained land, but sustained some 40,000 casualties in the first day. The British retreat continued the following day, but the French entered the Second Battle of the Somme on March 22.

The German offensive continued through March 26. The French were pessimistic, and were planning a retreat to protect Paris. This would have separated British and French forces. An Allied conference on the 26th placed French General Ferdinand Foch in command of the Western Front, with the goal of protecting the city of Amiens.

French and British efforts were eventually successful, and the German offensive was stopped. Losses on both sides were significant, with the Germans counting nearly 250,000 casualties and the British approximately 180,000. The Germans had gained a significant amount of land, but had not met any strategic goals.

The Sixth Bloodiest: The Third Battle of Ypres

The Third Battle of Ypres, often called the Battle of Passchendaele, took place between July and November 1917. The Allied goal was to regain control of land south and east of the Belgian city of Ypres; this goal was decided at Allied conferences in 1916 and early 1917. The Allies hoped to wear down the Germans, forcing them to keep fighting and preventing the potential for additional offenses. Regaining these lands would significantly weaken German supply chains and railway access, weakening their overall force. In addition, the Battle of Ypres would offer the opportunity to destroy German submarine bases, limiting submarine warfare.

The Allied offense launched in remarkably bad weather; torrential rains led to mud-soaked land. Men, cavalry horses, and artillery sank into the deep mud. Drownings were common, for both men and animals, and rifles and artillery were clogged by mud and water. The British were joined by forces from Australia and New Zealand in September, helping to provide essential support. In September 1917, the British gained the ridges east of the city of Ypres, making some gains. Canadian forces arrived following a call for help in October, and by early November, the tide of the battle was clear; the Allies would prevail. On November 6, British and Canadian forces captured Passchendaele.

The Battle of Passchendaele is one of the harshest examples of trench warfare in World War I. Specific counts of casualties are not agreed upon by scholars today; however, it is a fair estimate that each side of the battle lost more than a quarter of a million men to injury or death. Some scholars have suggested a number as high as 400,000 for German casualties, and around 300,000 for the British during the course of the three and one-half month battle.

The Fifth Bloodiest: The Gorlice-Tarnòw Offensive

Many Americans are completely unaware of this bloody battle, which resulted in a strong victory for the Central Powers, and a defeat for Russia and its allies. In early 1915, responding to cries from help from Austria-Hungary, Germany sent eight divisions to the Eastern Front, under the command of Hans von Seeckt. This began a period of significant successes for the Central Powers. In early May, the Gorlice-Tarnòw Offensive began. The Germans and Austro-Hungarians gathered outside Krakow, under the command of August von Mackensen.

The Offensive began on May 2, with heavy artillery fire. By May 3, the combined German and Austro-Hungarian force had taken some 17,000 Russian prisoners. By the 10th of May, in retreat, the Russian troops, originally numbering around 250,000, now numbered only 40,000. Within only days, the Germans and Austro-Hungarians had accomplished their goals, but chose to keep moving forward.

The Russians sent additional divisions to maintain control of the Carpathian Mountains; however, these divisions were so quickly defeated that they were, in essence, simply wiped off of the map. The Germans and Austro-Hungarians continued their advance, securing the Carpathian Mountains. The Germans continued, retaking Galicia in early June 1915. Galicia was home to many oil fields, providing an essential resource for the German navy.

The Gorlice-Tarnòw Offensive continued until June 22, 1915. For the Central Powers, this was an unbelievable success. They made huge gains, at a low cost. In total, the Central Powers sustained fewer than 90,000 casualties, including injuries, fatalities, and soldiers captured. The costs to the Russians have been estimated at nearly 8 times that figure, including some 250,000 Russian prisoners. The Gorlice-Tarnòw Offensive began a period on the Eastern Front known as the Great Retreat. By the end of the Great Retreat in September 1915, the front line had moved significantly further East, with the Central Powers making immense gains.

The Fourth Bloodiest: The First Battle of the Somme

The First Battle of the Somme was a five-month long battle, beginning on July 1, 1916. The Battle of the Somme primarily involved troops from the British Empire, including India and South Africa, and the Germans, but some French forces were also engaged in the fighting alongside the British. Australian forces also fought in the First Battle of the Somme.

A week prior to the start of the Battle of the Somme, the British began an artillery assault on Germans in the trenches near the Somme River. It was hoped that this would weaken German offenses; however, German troops and artillery were in deep trenches, and losses in the artillery assault before the Battle were limited. This led the British to underestimate the strength of German forces.

On the first day of the Battle of the Somme, the British suffered significant losses. The British had underestimated the French, and believed, quite strongly, that the force of 100,000 would be able to secure a quick victory. In total, the British lost 19,240 men on the first day of fighting, and another 57,000 were wounded. While the British had a very bad day on the first day, the French did make some progress against the Germans. The Allies gained three square miles of land on the first day, and continued their attack against the Germans in the coming days, making slow progress.

Within just a few days, the Germans were forced to call in reinforcements from troops in Verdun. By August of 1916, German casualties numbered 250,000; the German General Falkenhayn resigned; and food shortages were becoming common. In September 1916, the British brought tanks into the fight; gaining ground, but sustaining significant casualties. British gains continued, relying upon the strategy of the “creeping barrage,” in which artillery fire was used to clear a path for infantry troops to make slow progress. Fighting in the offensive ceased on November 19, 1916.

The First Battle of the Somme was a victory for the Allies, but it was a victory at an astonishing human cost. In total, there were well over one million casualties in this battle, counting the British, French and Germans.

The Third Bloodiest: The Spring Offensive

Fundamentally, the Spring Offensive was an attempt by German forces, under the command of Ludendorff, to end World War I with a German victory. The path to the Spring Offensive was cleared by the withdrawal of the Russians from World War I following the October Revolution, ending fighting on the Eastern Front. This freed some 500,000 German troops for service on the Western Front. The British and French attempted to prepare for the attack, but were well aware of the weaknesses in their own defenses.

The initial attack in the Spring Offensive came to the west of Cambrai, with a massive artillery assault beginning on March 21, 1918. The Germans advanced rapidly and successfully through the British Fifth Army, following the artillery assault with a division of elite troops, carrying weapons designed to cause fear. The Germans regained land lost in the Battle of the Somme, and brought large cannons within range of the city of Paris; shelling of the city began at once. German troops were ordered to take the city of Amiens; however, the assault and offensive began to fail due to supply line issues.

The Spring Offensive looked to be a great success in March, with the Germans declaring March 24 a holiday in celebration of their early successes. The Americans arrived on the Western Front at the end of March, and while there were some conflicts over command responsibilities, this was the German army’s worst-case scenario. By April, the Germans had suffered 230,000 casualties. By July 15, the Spring Offensive was over. German casualties numbered nearly one million, and Allied casualties around half that. The Americans had turned the tide of war, and were, by the end of the Spring Offensive, arriving in numbers totalling several hundred thousand each month.

The Second Bloodiest: The Hundred Days Offensive

The Hundred Days Offensive is the final significant military effort of World War I. Between the 8th of August and the 11th of November 1918, the Allies initiated a series of offensives against the Central Powers. This followed the Spring Offensive. With the end of the Spring Offensive, the Allies planned a number of counter-offensives, under the command of French general Ferdinand Foch. By this time, there were large numbers of American troops available, and British reinforcements for the Western Front had returned from campaigns in Palestine and Italy.

The Hundred Days Offensive began with the Battle of Amiens, eventually leading to a retreat by the Central Powers and the armistice that ended World War I. The Battle of Amiens, beginning on August 8, was a remarkable success. A huge number of troops, as well as some 500 tanks, took the Central Powers entirely by surprise. Attacking from the rear, the Allies created a 15-mile break in the German lines. By the 10th of August, the Germans began to retreat to the Hindenberg Line.

The Allies continued their counter-offensives, progressively pushing the Germans further and further back toward and behind the Hindenberg Line. The Hindenberg Line was a defensive border established by the Germans in the winter of 1916 and 1917. A series of offensives, sometimes called the Grand Offensive, directly attacked the Hindenberg Line. As the Allied armies continued to push German troops further and further back toward Germany, supply lines were significantly impaired, further weakening the Germans. The fighting continued until only moments before the armistice was signed on November 11, 1918.

There are no exact figures for casualties in the Hundred Days Offensive, but estimates suggest 700,000 Allied casualties, including injuries and fatalities. German casualties numbered at least 760,000; however, many scholars believe that number is quite low. In addition, as a loss became self-evident, large numbers of German soldiers deserted.

The Bloodiest Battle of World War I: The Brusilov Offensive

The Brusilov Offensive began with the Battle of Lutsk on June 4, 1916. The Brusilov Offensive is named after the greatest Russian general Alexei Brusilov. When the Germans began to attack the fortress city of Verdun, France, the French requested aid from their Allies. The goal was simple; the Allies would engage the Central Powers at other sites and locations, weakening their resources for the attack on Verdun. In March 1916, Brusilov received permission to begin engaging with the Germans and Austro-Hungarians, outside of other planned offensives.

The Brusilov Offensive began with a strong artillery attack on Austro-Hungarian troops near the city of Lutsk, in modern-day Ukraine. This is a tactic used by other Allies later in the War, and used with particularly great success by the Germans. The front was some 200 miles in length. Austro-Hungarian troops outnumbered Brusilov’s Russian forces; however, the use of artillery brought a rapid Russian victory in Lutsk. Within two days, the Russians inflicted 130,000 casualties on Austria-Hungary, forcing changes to the Austrian military strategy. By the 15th of June, the Germans were pulling troops from the Western Front to support Austro-Hungarian troops under attack by Brusilov’s forces.

Brusilov’s initial victory was followed by a series of additional successes, through the summer of 1916. Eventually, Russian resources began to run out, ending the remarkably successful Brusilov Offensive by mid-September of that year. This Russian victory is often forgotten, particularly since it was so soon followed by the chaos of the Russian Revolution.

Brusilov inflicted a destructive toll on the armies of Austria-Hungary. The Central Powers lost approximately one million men, and another 400,000 were captured. Russian casualties numbered between 500,000 and one million, making this the bloodiest battle of World War I.

Where did we find this stuff? Here are our sources:

“World War One: The Global Conflict that Defined a Century.” BBC History. 2018.

“World War I by the Numbers.” History Channel.

“World War I.” HistoryNet. 2018.