The underlying causes of the war of 1914 -18 were many and varied. For many years the great powers of Europe were suspicious and fearful of each others motives. Germany, after unification in 1870, had slowly become the bully of Europe. The Prussian military caste and the Kaiser, Willhelm II, were arrogantly bent on creating a Europe that would be the most powerful nation in Europe. Germany's domineering fist and, in their own sphere, the smaller paws of her weaker partner Austria-Hungary were a standing provocation. Austria and Russia were rivals in the Balkans. Germany and Russia were rivals in the Near East, where the former had gained a dominant influence over Turkey. France was still recovering from her crushing defeat in the Franco-Prussian war of 1870 - 71, as well as from later humiliations. As for Britain, while Germany's designs in the Near East challenged her interests there, Germany's ambitious naval plans threatened her very existence.
By 1907 the uneasy powers had formed themselves into two opposing groups. Germany, Austria-Hungary and Italy made up the Triple Alliance. Britain, France and Russia had come together in the Triple Entente to balance it. This had developed from the historic Entente Cordiale, established between Britain and France in 1904. In 1914 Europe was heading like a speeding train out of control straight for the abyss of war, and all Britain's desperate efforts to apply the brakes were powerless. What precisely Germany's ambitions were, and whether she was spoiling for a fight, are even now disputed questions. She was the strongest military power in Europe. Her neighbors feared her aim was to dominate them. Germany feared that the Triple Entente sought her destruction.
The spark that lit the fuse that fired the gun that shattered Europe was a relatively trivial event. At Sarajevo on 28th June 1914, Gavrilo Princep, a young Serb nationalist, assassinated the heir to the Austro-Hungarian throne Archduke Franz Ferdinand. Austria, with some show of reason, blamed Serbia for the crime and declared war on her. Russia, Serbia's patron, prepared to come to her aid. Germany, supporting Austria, declared war on Russia and France. Britain entered the war on August 5th, after Germany invaded Belgium, ignoring the small country's guaranteed neutrality and in doing so becoming a direct threat to Britain's maritime security. Europe had now committed herself to a war, a war that would be fought on a new and devastating scale. The combatant nations throwing all their resources in a fight to the death: men by the million; the new airplanes and ships; improved submarines; heavier artillery and more machine guns; poison gas; and Britain's new invention the tank.
Germany had to cope with a war on two fronts. The nature of the alliance system ensured that Russia was allied with Britain and France, set against Germany's alliance with Austria-Hungary and Italy. She counted on a swift victory and acted on the preconceived Schlieffen Plan. This was to strike through Belgium, sweep round towards Paris, envelop the French armies in a pincer movement and destroy them and so bring France to her knees before the slow moving Russian armies were ready to engage. The plan might have succeeded if it had been followed explicitly. The Belgium frontier fortresses collapsed. The French in the north and the British Expeditionary Force under Sir John French on their left flank were in danger of being surrounded. The British stands at Mons and La Cateau enabled them to extricate themselves, but by the end of August the German army were in striking distance of Paris. It was then that the Germans, overrating their successes, made a false move and Joffre, the French Commander, saw that they paid for it. On the 5th September he turned and counter attacked and drove the startled enemy back from the River Marne and across the Aisne. This was the famous 'Miracle of the Marne' that saved Paris and perhaps France.
In Belgium, the fall of Antwerp on October 9th was followed by a German drive for the Channel ports, the possession of which would of cut off Britain's communications. Britain counter attacked and blocked the German advance at Ypres. In a series of battles that raged with unsurpassable fury from October 19th to November 22nd, the British fought the enemy to a standstill. The german hopes of a swift victory were shattered. The struggle became static along a 350 mile line of trenches stretching from the North Sea to Switzerland. The Allies had suffered over a million casualties.
In the East the Russians were experiencing a mixture of defeat and victory. In East Prussia they were soundly beaten in the Battle of Tannenberg. In the South they defeated the Austrians at Galacia.
In 1915 the deadlock on the Western Front led the Allies to concentrate their efforts in the East. Turkey had joined the enemy powers in October 1914; whereupon Britain had annexed the island of Cyprus and declared Egypt a British protectorate. Russia was under a lot of pressure and a plan was formed for forcing the Dardanelles and taking Constantinople. This would eliminate Turkey in Europe and enable aid to be sent to Russia. When a naval bombardment failed to silence the forts, troops were landed on the Gallipoli peninsula. It was an operation of immense difficulty and only the bravery and resoluteness of the attackers, especially the 'Anzacs' from Australia and New Zealand made it possible. Even so the valour of these remarkable men was of no avail. Due to incompetent staff work and bad luck the offensive was abandoned at the end of the year. More than 600,000 Turkish and British Commonwealth troops lost their lives in the campaign.
During this time Turkey in Asia was receiving attention. Indian divisions advanced up the River Tigris in Mesopotamia (Iraq) and in September captured Kut. There however, General Townshend was later besieged by a superior force. All attempts to relieve him were repulsed and in April, 1916, after a siege of nearly five months, the garrison was forced to surrender. 3,000 British and 6,000 Indian troops were taken prisoner.
In 1916 Britain realised that she must use all her resources to make good the appalling casualties suffered by the allies. The Asquith government was forced to introduce conscription under the Military Service Act. In the same year Falkenhayn, the German commander, worked on the idea of bleeding France to death by continuous assault on a vital point. From February to September he battered away at the great fortress system of Verdun. France did indeed bleed, but not to death. General Haig relieved the pressure on the fortress by a sustained offensive in the Somme Valley, and Verdun remained untaken. The casualty total for Verdun has been estimated at over 700,000.
The Battle of the Somme, 1st July to 18th November 1916 was a defining moment. The enemy's lines were so shaken that the Germans were forced to retreat to what is known as the Hindenburg line. On the first day the British suffered 57,470 casualties, mostly young volunteers. This loss of life had a deep cultural impact on Britain's perception of warfare and the Western Front. The first use of tanks took place in September. The attacks on both sides continued through to November, in appalling conditions. Casualties have been disputed, but were probably about 400,000 each, German and British, and 200,000 French. This was the catastrophe that gave rise to the slogan 'Never Again' and convinced the British Prime Minister, Llyod George, of his general's incompetence and confirmed his hostility to General Haig.
The year 1918 brought the long and bitter conflict to a crisis. Ludendorff, who had taken over the German command in the West, massed all his forces for a determined attempt at victory before the American armies were ready. The submarine campaign had failed and the British blockade was succeeding. From March to July Ludendorff delivered a series of attacks that were savagely driven home. The Allied armies reeled before the staggering blows, the British front was pierced and the onrushing Germans once more reached the Marne. This was to be their final effort and Foch, now Supreme Commander in France, was able to strike back. Then, on 8th August , in the Somme area, Haig, with 450 tanks supporting his troops, launched an offensive that broke the German front and scored a spectacular triumph. The victory was followed up by repeated stabbing attacks all along the German lines and the enemy were forced back in a general retreat. On 11th November Germany surrendered and signed armistice terms dictated by the victors. The Allies, with the British Commonwealth and Empire forming the hard core of their exertions, had won what was perhaps the most titanic war in history.
Germany was disarmed and forbidden to re-arm. She was presented with a colossal, and near impossible, war bill. The Treaty of Versailles 1919 redrew the map of Central Europe with the aim of securing the liberation of the smaller countries from their former masters and converting them into new democratic states. The Austro-Hungarian empire had already broken up. From it the republics of Austria, Hungary and Czechoslovakia were formed. Republics were also set up in Germany, Poland, Yugoslavia and the Baltic countries. The victorious powers laboured to prevent further armed conflicts by means of a League of Nations. A solemn covenant, signed by member states all over the world, was made to submit future disputes to arbitration and to combine forces against any aggressor.