World War One
The war to end all wars
28 July 1914 - 11 November 1918

The First Word War, also known as the Great War or The War to End All Wars was a global war that originated in Europe, lasting from 1914 until 1918. Over 9 million soldiers and 7 million civilians died as a result of the war. The causes of the war are complex: colonial rivalries, economic competition and irreconcilable national ambitions were some of the contributing factors. The war was triggered by the assassination of Austro-Hungarian Crown Prince Franz Ferdinand by the Serb nationalist Gavrilo Princip at Sarajevo. This triggered a series of diplomatic crises, when Austro-Hungary delivered an ultimatum to Serbia whose contents the Serbs deemed unacceptable. Soon all the major European powers became involved in the affair, on one side or the other. Ultimately, the crisis could not be resolved and war was declared.

The war was fought between the powers of the Triple Entente - the French Republic, Russian Empire and the British Empire - and the Central Powers, composed of the German and Austro-Hungarian Empires. As the war progressed other nations joined one side or the other: the United Sates, Japan, Italy and Romania joined the Entente powers and Bulgaria and the Ottoman Empire joined the Central Powers.

When the war ended the world had changed as well: the Russian, German, Ottoman and Austro-Hungarian Empires were no more, and many nations faced revolutions or other wars that would define them. National borders were redrawn, as some nations regained their independence, while some enlarged their territories at the expense of the losing states. At the Paris Peace Conference in 1919 the United States, France, Britain and Italy imposed their will upon the defeated nations. The League of Nations was formed with the aim of preserving peace. However, economic disaster, feelings of nationalism and humiliation, especially in Germany, doomed the League to failure and contributed to the start of World War II.

Introduction
German attack

The First World War started with the German invasion of South Belgium and eastern France in what would collectively be known as the Battle of the Frontiers. These titanic clashes began with the German invasion of Belgium. Here the Germans advanced quickly, capturing Liege and Brussels, despite a French counterattack. The main French mobilization, however, took place in Alsace-Lorraine. There the French organized a offensive which, despite some early successes, turned into a disaster for the French Army. The disaster was repeated in another ill-conceived French attack, in the Ardennes area. For the British, the war began just as badly, when they were forced to conduct a fighting retreat at Mons. The Battle of the Frontiers did not go well for the Entente forces, who were forced to retreat on the river Marne, on the outskirts of Paris.

Entente counterattack and stalemate

The first battle of the war had gone well for the Germans: in France the Entente forces were retreating on the river Marne, and the Germans had captured a large part of Belgium. Victory seemed to be in the Germans’ grasp when the Entente forces, under the direction of French General Joseph Joffre, organized a vast counterattack along the Marne, which forced the Germans into retreat. The next phase of the fighting has often been described as the ‘Race for the Sea’. This ‘race’ actually consisted of a series of outflanking maneuvers, in which both sides sought, not to reach the sea, but to get round the northern flank of their opponent. The ‘race’ ended when Belgian troops, on the North Sea coast of Belgium, occupied the last open area of the front. The Belgians had retreated from the city of Antwerp which had fallen to the Germans. The Germans made one last attempt to break open the Entente front, at Ypres, in Western Flanders. The battle proved to be indecisive because, by this point, both sides began constructing heavy defensive fortifications: trench warfare had arrived on the Western Front.

First Entente offensives

After the end of the German offensive at Ypres, both sides were exhausted after months of fighting. With the onset of winter the French organized a few limited attacks against strong German positions, with little to no effect on the front’s situation. In this period a curious event took place that is well known even today: the Christmas truce. In some sectors of the front, during the winter holiday, enemy soldiers crossed into No Man's Land exchanging food and cigarettes, singing carols, and even playing football. This temporary romantic distraction did not last, and in the spring of 1915 hostilities resumed when the Entente forces organized a series of attacks at Artois, Ypres and Arras. By this time, the Germans had constructed heavy defensive fortifications, and the French and British had neither the tactical sophistication nor the numbers of artillery shells needed to break open the German lines. Entente operations resumed in the autumn with new attacks at Artois, Champagne and Loos. These too ended in bitter failure, as casualties on both sides mounted.

Attrition warfare on the rise

During 1916 a tactical deadlock developed on the Western Front of World War One: since neither side had the necessary force to break open the other’s defences, a new strategy was adopted whereby both sides tried to grind down the enemy, inflicting as many casualties as possible so as to bring the enemy force to the point of exhaustion. The Germans tried this strategy during the Battle of Verdun, a year-long battle in which they tried to force the collapse of the French Army. In the end this did not succeed, and the Germans suffered almost as many casualties as the French, with little to show for it in terms of gained ground on the battlefield. In order to relieve pressure on the French, the British launched an attack on the German positions on the Somme. The first day of the Somme was the greatest disaster suffered by the British army on the Western Front, with very heavy casualties. At the end of the battle, the British and French had penetrated some 10 km into German occupied territory, taking more ground than in any of their previous offensives since 1914, but at the cost of hundred of thousands of casualties.

German tactical retreat and new Entente offensives

In the beginning of 1917 the German Army executed Operation Alberich, a planned withdrawal to the shorter and thus more easily defensible Hindenburg Line. The withdrawal eliminated two salients which had been formed in 1916 during the battle of the Somme. The next major battle would come in the spring. It was planned by the new French Chief-of-Staff, Robert Nivelle. The Nivelle offensive attacked German positions in the Arras area and on the Aisne. When the battle, which was intended to achieve a decisive breakthrough, failed to break open the German lines, it was suspended. In the aftermath of the failed offensive, some elements of the French Army, brought to the point of physical and mental exhaustion, mutinied because they were no longer willing to participate in ill-conceived offensives that would cost even more lives. After the collapse in morale of the French Army, the British organized a series of attacks in Flanders for the rest of the year. The results of the battles in Flanders are disputable: while the British did manage to capture some territory from the Germans, they sustained heavy casualties, which would have been unsustainable if the war continued as before.

Maneuver warfare returns

At the end of 1917 it was clear that if the Entente wanted to win they would have to change their strategy, as the Germans were still undefeated after years of constant attacks in which millions of soldiers had lost their lives. In order to break the deadlock, the British deployed hundreds of tanks on the battlefield around the town of Cambrai, an important German supply point. This was the first time tanks were used in such concentrated numbers. Initially the gamble paid off and the British advanced some 6 kilometers, but then the mechanical unreliability of the tanks slowed the British advance to a crawl. An immediate counterattack followed, and the Germans, employing a new artillery bombardment technique that allowed for much greater mobility, stopped the British advance and regained some lost ground. In the spring of 1918 the Germans tried to defeat the Entente forces before the Americans could arrive in force on the front. Using new artillery bombardment techniques, the Germans managed to break the stalemate on the Western Front, and in their Spring Offensive they advanced all across the front, creating vast salients in the British and French lines. However, they did not manage a decisive breakthrough, as Entente forces successfully defended Paris in the Second Battle of the Marne. The German defeat on the Marne marked the beginning of the relentless 100 Days Offensive, initiated by the Entente forces, that ended the war.

Final Entente offensives. Defeat of the German army and the end of the war

The Hundred Days Offensive was the final series of battles in World War One. During these battles the Entente forces launched a series of attacks against the German Army all along the Western Front. Beginning with the Battle of Amiens, and continuing with attacks at Albert, on the Somme, in the Argonne and in Belgium, at Ypres, the offensive pushed the Germans out of France, forcing them to retreat beyond the Hindenburg Line. The Hundred Days offensive ended the war with the Armistice of 11 November 1918.

First Russian offensives

The Eastern Front of World War One began with a declaration of war between the Germans, together with their Austro-Hungarian allies, and the Russians. The first battles took in Eastern Prussia. Russia invaded the German territory as a means of distracting the Germans from the Western Front and forcing them to redirect troops to the East, thus providing an indirect aid to the French and British who were struggling in the West. The Russians attacked before they were truly ready, and with severe deficiencies the Russian Army suffered devastating losses at the battles of Tannenberg and Masurian Lakes. In Galicia, the then Austro-Hungarian province was defended by the weak Austro-Hungarian Army. Thus, the Russians managed to capture the city of Lemberg, today Lviv, and ruled the province for nine months until their defeat during the Gorlice-Tarnów Offensive.

Central Powers success and Russian retreat

When spring came again on the Eastern Front, the Germans and Austro-Hungarians planned a new offensive. Originally, the Gorlice-Tarnów Offensive was designed to relieve pressure on the southern part of the Austro-Hungarian front. Because it was so successful it was reorganized as the major offensive operation for the Central Powers on the Eastern Front during 1915. During the battles that followed, the Russian lines collapsed and the Tsar’s army had to retreat into Russia. Although this retreat, known as the Great Russian Retreat, was well conducted, it was a severe blow to Russian morale.

Renewed Russian success

At the beginning of 1916 the Russians knew that they had to regain the initiative on the front if they were to secure victory. As such they started to prepare for a new general offensive. But the French were in deep trouble at Verdun on the Western Front, so French Marshal Joseph Joffre requested that the Russians move as soon as possible in order to relieve pressure on the French troops. So it was that the Russians launched the Lake Naroch Offensive before they were truly ready. The result was predictable and the operation failed. The situation changed during the summer when General Alexei Brusilov launched his famed offensive. Using new tactics, Brusilov’s troops inflicted a severe defeat, especially on the Austro-Hungarians.

Russian Revolution and victory for Germany

At the beginning of 1917, Russia was a country in turmoil: almost three years of war had brought the army to the point of exhaustion. The Russians had suffered millions of dead and victory was still a far cry. Meanwhile the civilian population was suffering from hunger and there was widespread discontent against the monarchy. In the Russian capital, Petrograd, a mass protest over food rationing started: the February Revolution had begun. In the end, Tsar Nicholas II had to abdicate his throne. A new Russian Provisional Government was formed, which was heavily influenced by the Bolsheviks. Afterwards, the Provisional Government turned its attention to the front and tried to organize a new offensive against the Central Powers. This offensive failed because the Russian Army was beginning to collapse. Many units simply refused to fight because of the strong revolutionary spirit that had taken hold in Russia. The Germans took advantage of the situation and attacked, regaining all of the ground lost during the previous summer, plus the city of Riga. After the Germans took Riga, the Bolsheviks seized the moment and organized the October Revolution during which they stormed the Winter Palace in Petrograd, the seat of power for the Provisional Government. The success of the revolution marked the end of hostilities on the front, as an armistice was put in effect. Ultimately a peace was signed at Brest-Litovsk between the Central Powers and the Russians in the spring of 1918. The treaty was a significant victory for the Germans. However, because they were defeated on the Western Front a few months later, the treaty was terminated.

Balkans Front
Middle Eastern Front