The First World War was truly ‘the Great War’. Its origins were complex. Its scale was vast. Its conduct was intense. Its impact on military operations was revolutionary. Its human and material costs were enormous. And its results were profound.
The war was a global conflict. Thirty-two nations were eventually involved. Twenty-eight of these constituted the Allied and Associated Powers, whose principal belligerents were the British Empire, France, Italy, Russia, Serbia, and the United States of America. They were opposed by the Central Powers: Austria-Hungary, Bulgaria, Germany, and the Ottoman Empire.
The war began in the Balkan cockpit of competing nationalisms and ancient ethnic rivalries. Hopes that it could be contained there proved vain. Expansion of the war was swift. Austria-Hungary declared war on Serbia on 28 July 1914; Germany declared war on Russia on 1 August. Germany declared war on France on 3 August and invaded Belgium. France was invaded on 4 August. German violation of Belgian neutrality provided the British with a convenient excuse to enter the war on the side of France and Russia the same evening. Austria-Hungary declared war on Russia on 6 August. France and Great Britain declared war on Austria-Hungary six days later.
The underlying causes of these events have been intensively researched and debated. Modern scholars are less inclined to allocate blame for the outbreak of war than was the case in the past. They have sought instead to understand the fears and ambitions of the governing élites of Europe who took the fateful decisions for war, particularly that of imperial Germany.
Fears were more important than ambitions. Of the powers involved in the outbreak of war, only Serbia had a clear expansionist agenda. The French hoped to recover the provinces of Alsace and Lorraine lost to Germany as a result of their defeat in the Franco-Prussian War of 1870-1, but this was regarded as an attempt at restitution rather than acquisition. Otherwise, defensive considerations were paramount. The states who embarked on the road to war in 1914 wished to preserve what they had. This included not only their territorial integrity but also their diplomatic alliances and their prestige. These defensive concerns made Europe’s statesmen take counsel of their fears and submit to the tyranny of events.
The Austrians feared for the survival of their multi-racial Empire if they did not confront the threat of Serb nationalism and Panslavism. The Germans feared the consequences to themselves of allowing Austria, their closest and only reliable ally, to be weakened and humiliated. The Russians feared the threat to their prestige and authority as protector of the Slavs if they allowed Austria to defeat and humiliate Serbia. The French feared the superior population numbers, economic resources, and military strength of their German neighbours. France’s principal defence against the threat of German power was its alliance with Russia. This it was imperative to defend. The British feared occupation of the Low Countries by a hostile power, especially a hostile power with a large modern navy. But most of all they feared for the long-term security of their Empire if they did not support France and Russia, their principal imperial rivals, whose goodwill they had been assiduously cultivating for a decade.
All governments feared their peoples. Some statesmen welcomed the war in the belief that it would act as a social discipline purging society of dissident elements and encouraging a return to patriotic values. Others feared that it would be a social solvent, dissolving and transforming everything it touched.
The process of expansion did not end in August 1914. Other major belligerents took their time and waited upon events. Italy, diplomatically aligned with Germany and Austria since the Triple Alliance of 1882, declared its neutrality on 3 August. In the following months it was ardently courted by France and Britain. On 23 May 1915 the Italian government succumbed to Allied temptations and declared war on Austria-Hungary in pursuit of territorial aggrandizement in the Trentino. Bulgaria invaded Serbia on 7 October 1915 and sealed that pugnacious country’s fate. Serbia was overrun. The road to Constantinople was opened to the Central Powers. Romania prevaricated about which side to join, but finally chose the Allies in August 1916, encouraged by the success of the Russian ‘Brusilov Offensive’. It was a fatal miscalculation. The German response was swift and decisive. Romania was rapidly overwhelmed by two invading German armies and its rich supplies of wheat and oil did much to keep Germany in the war for another two years. Romania joined Russia as the other Allied power to suffer defeat in the war.
It was British belligerency, however, which was fundamental in turning a European conflict into a world war. Britain was the world’s greatest imperial power. The British had world-wide interests and world-wide dilemmas. They also had world-wide friends. Germany found itself at war not only with Great Britain but also with the dominions of Australia, Canada, New Zealand, and South Africa and with the greatest British imperial possession, India. Concern for the defence of India helped bring the British into conflict with the Ottoman Empire in November 1914 and resulted in a major war in the Middle East. Most important of all, perhaps, Britain’s close political, economic, and cultural ties with the United States of America, if they did not ensure that nation’s eventual entry into the war, certainly made it possible. The American declaration of war on Germany on 6 April 1917 was a landmark not only in the history of the United States but also in that of Europe and the world, bringing to an end half a millennium of European domination and ushering in ‘the American century’.
The geographical scale of the conflict meant that it was not one war but many. On the Western Front in France and Belgium the French and their British allies, reinforced from 1917 onwards by the Americans, were locked in a savage battle of attrition against the German army. Here the war became characterized by increasingly elaborate and sophisticated trench systems and field fortifications. Dense belts of barbed wire, concrete pillboxes, intersecting arcs of machine-gun fire, and accumulating masses of quick-firing field and heavy artillery rendered manœuvre virtually impossible. Casualties were enormous.
The first phase of the war in the west lasted until November 1914. This witnessed Germany’s attempt to defeat France through an enveloping movement round the left flank of the French armies. The plan met with initial success. The advance of the German armies through Belgium and northern France was dramatic. The French, responding with an offensive in Lorraine, suffered an almost catastrophic national defeat. France was saved by the iron nerve of its commander-in-chief, General J. J. C. Joffre, who had not only the intelligence but also the strength of character to extricate himself from the ruin of his plans and order the historic counter-attack against the German right wing, the ‘miracle of the Marne’. The German armies were forced to retreat and to entrench. Their last attempt at a breakthrough was stopped by French and British forces near the small Flemish market town of Ypres in November. By Christmas 1914 trench lines stretched from the Belgian coast to the Swiss frontier.