The centenary of the armistice in November 1918 that effectively brought World War I to a close has drawn less attention, particularly in the United States, than the anniversary of its outbreak four years before. A series of major scholarly books with crossover appeal to the general reader explored the origins of World War I with Christopher Clark, Max Hastings, and Dominic Lieven making important contributions to an ongoing debate about a pivotal moment. Europe had been spared a general war among great powers since Napoleon’s defeat at Waterloo in 1815, and the conflict unleashed by the guns of August 1914 exhausted protagonists while shattering old certainties. Like Humpty Dumpty in the nursery rhyme, the pieces could not be put back together again.

Not surprisingly, scholars and public alike have focused on what caused World War I. How could leaders have let the catastrophe happen? Why did they choose steps that escalated tensions and embraced the unpredictable risks war involves? Indeed the general question of how wars begin has been a longstanding concern for academics studying international relations. Answering it promises insight on managing crises to stop their escalation. Fewer studies examine how wars end. Understanding the costs of World War I and its lingering impact after 1918 required considering why belligerent powers chose not to cut their losses by negotiating a compromise. Prolonging the war after it reached a stalemate turned the struggle into an attritional struggle that drove societies beyond their breaking point and made later stability elusive.

Understanding How Wars End

Wars end more often in a negotiated peace than a clear victory where one side dictates terms to a defeated foe. Indeed, the Peace of Westphalia that created the modern state system in Europe came from a stalemate in the brutal Thirty Years War (1618-1648). Compromise to produce a peace of exhaustion served all sides better than continuing the struggle. Mounting costs and the inability of a coalition against France to force a breakthrough prompted negotiations that ended the War of Spanish Succession (1701-1714) on acceptable terms with both sides conceding aims. Sometimes, as following the War of Austrian Succession (1740-1748), peace left underlying questions unresolved to produce a truce that allowed belligerents to recover for the next round instead of a lasting settlement. More often, as the historian Paul Schroeder notes, agreements ending wars provided the basis for a decade or two of general peace founded on the acknowledgment of legitimate interests. The Napoleonic Wars (1803-1815), fought until Napoleon’s defeat after his opponents realized they could not make peace with him on acceptable terms, marked an exception illustrating that general rule. Exhaustion from that struggle contributed to the long peace nineteenth century Europe enjoyed.

Neither military leaders nor their political masters planned for a long war in 1914. German and French plans aimed at fighting a decisive battle in the west to avoid the kind of prolonged struggled they might lose. Rather than being home by Christmas, or even before the leaves fell, armies on both sides fell short of their objectives with heavy losses. Trench warfare on the Western Front brought stalemate by the end of the year, with a similar pattern in the open regions of Eastern Europe. Neither side had compelled the other to accept its terms. Why not cut losses by compromising to secure peace?

Human costs incurred by 1915 made compromise hard, especially as public opinion rallied around governments on both sides in a spirit of national unity. Russian leaders took a hard line in the July Crisis as they feared another political defeat would turn the people against the Tsarist regime. Two French corps lost around 60,000 men in an August 1914 clash along the Sambre River alone. Austria-Hungary’s army never recovered from casualties among junior officers whose prewar experience could not be replaced. German reservists, including students fired by patriotic élan, fell in such numbers that battles around Ypres during the autumn became known as the Kindermord or massacre of the innocents. Something had to be won for those sacrifices to make sense. War aims took shape partly in that context. Retreating from them seemed a betrayal that threatened the legitimacy of rulers no less than outright defeat.

Even as a strategy for victory became increasingly elusive, belligerents chose to double down rather than negotiate a compromise settlement. Both sides used technologies, including poison gas, massed artillery, and later tanks to break the deadlock. Germany used attritional tactics at Verdun by inflicting unsustainable casualties with hopes the French army would break. France and Britain mobilized imperial manpower to support their war effort while imposing a blockade that limited the Central Powers to resources they directly controlled. Food and material shortages followed that strained the home front and industrial production. Acting for the first time as a military great power in fielding an army on the scale of continental rivals with a larger population, Britain departed from its traditional maritime focus in ways that dislocated its home economy and public consciousness. None of these steps, however, provided the breakthrough each side desperately sought.

The Allies They Needed

Bringing new partners into each alliance similarly failed to change the dynamic. Leading powers—Britain, France, and Germany—carried a heavy burden in supporting allies whose efforts faltered. Alliance dynamics made compromise harder because any overture risked defections by allies cutting their own deal. Even publicly discussing war aims posed dangers that Britain’s foreign secretary Sir Edward Grey described in a syllogism. The allies needed Britain to win or even keep fighting, while British security required victory or at least substantially weakening Germany. Able to gain more tolerable terms than Britain, allies depended less on checking Germany for their security. Grey therefore concluded that the British relied more on their allies than the allies relied on Britain. Similar considerations made other powers careful in discussing war aims lest they alienate partners.

Failed peace overtures in 1917 between Britain and Austria-Hungary showed the dynamic at work. Prime Minister David Lloyd George privately hoped that Austria might break with Germany, and Charles sought peace to end pressures the Habsburg Monarchy could no longer bear. But a deal risked alienating Italy, unless it held the Austrian lands it claimed as a reward for joining the war. Vienna also had become too reliant on its German partner by then to chart a separate course. Peace feelers at different points over the year made no progress. When a secret meeting in Switzerland in early 1918 showed Austria would not make peace alone, the British gave up a separate peace and accepted its eventual partition among subject nationalities in return for their support. Germany had already determined on an offensive that spring to end the war before the United States could bring its forces to bear.

By then, Russia had collapsed into revolution and civil war. Berlin had pushed the United States in 1917 from neutrality to intervention by escalating its use of submarines to disrupt allied shipping. Having financed the war by inflation and squeezing its civilians at home, Germany faced increasing difficulty sustaining its efforts. Victory on the Eastern Front provided a temporary breathing space. An offensive along the Western Front pushed allied forces back until May when they held a line and then counterattacked the German army whose combat effectiveness never recovered.

Germany’s Plight

The collapse of Germany’s allies from September 1918 made its own position increasingly untenable. Requesting a ceasefire with hopes of dividing the allies only accelerated pressures that forced the Germans within weeks to accept whatever terms they were offered. The army by then had declared itself unable to continue fighting and William II abdicated the throne. A civilian government bore the responsibility for an armistice that amounted to surrender. German generals claimed their army had been undefeated and was stabbed in the back by civilians. This Dolchstosslegende combined with the perception of a punitive peace settlement poisoned Germany’s politics. While the terms dictated at the Versailles Conference were far from the Carthaginian peace John Maynard Keynes famously alleged, they did stipulate Germany’s responsibility for the war, impose financial reparations, and transfer formerly German territory to France and Poland. Efforts by German governments to evade or revise the treaty undermined postwar stability, especially as other dissatisfied powers sought changes of their own.

How the war ended in 1918 mattered less than the fact that it lasted that long and strained many combatants to the breaking point. Russia collapsed into anarchy under the pressure of repeated military defeat and social unrest in cities struggling with food shortages as former interior minister Petr Durnovo predicted in February 1914. Austria showed far more cohesion than many anticipated, but it shattered leaving a rump German-speaking republic barely able to feed it population. Besides severing economic links within the single market the Habsburg Monarchy had provided, breaking Austria into a collection of small countries left a power vacuum in the Danubian basin that Germany and Russia would later compete to fill.

France itself had suffered massive economic damage, compounded by Russia’s default on prewar loans. The war’s demographic impact from both casualties and low wartime birthrates had a lingering impact on several levels, including public confidence. A smaller pool of manpower forced a cautious approach to strategy and foreign policy in the 1930s along with technological fixes like the Maginot Line. British military losses contributed to shattering Edwardian self-confidence as global financial ascendancy passed to the United States. Although the allied powers besides Russia and to a lesser degree Italy fared better than their adversaries, victory did not spare them from paying a price. Even the United States faced dislocation that culminated in a postwar red scare. Not surprisingly, Warren Harding campaigned successfully for the presidency on the slogan of a return to normalcy.

But just as the war, in George Kennan’s perceptive assessment, limited the options for diplomats and statesman for decades, so it also made normalcy elusive. The changes war had brought over a short time had been too great. Members of law-abiding, peaceable societies in Central Europe operating under a rule of law that constrained the state along with its subjects brought home a tolerance for violence they had acquired in combat. Ernst Jünger’s glorification of combat in his memoir Storm of Steel struck a chord among many in his generation. Veterans—and younger brothers who had not served but looked up to them—filled the ranks first of paramilitary Freikorps and later the National Socialist and Fascist parties. Government in Germany had become militarized behind the scenes, while ethnic conflict elsewhere prompted fighting. Chaos in Russia cast a shadow as émigrés brought tales of Bolshevik atrocities and political murder that alarmed the middle and upper classes along with peasants. Attempted revolutions in Hungary and Germany brought a swift backlash that normalized political violence and encouraged further polarization. Under pressure, the center did not hold.

Undermining social and political stability created a space for radical cultural alternatives at the same time conflict had normalized violence for many Europeans. The sheer weirdness of dropouts in post-1918 Germany who seized upon dislocation to compete for a following with apocalyptic claims illustrates a pattern with prewar roots that metastasized in the 1920s and found echoes in other countries. Adolf Hitler was only the most successful among many aspiring messiahs, as Michael Burleigh points out in his study of politics and religion during the twentieth century. Politics in certain forms acquired many religious trappings from public rituals to a search for transcendence and the conviction that error had no rights. Irrationalism and political extremism became hallmarks of postwar Europe that cast a longer shadow which still lingers.

World War I’s impact derives largely from its duration. Prolonged fighting changed societies and rendered governments less able to buffer them from shocks the conflict imposed. The hubris of risking war and then doubling down on the bet in pursuit of victory brought nemesis for the German, Austrian and Russian empires along with dislocations that affected even the victorious powers. While generations have commemorated the sacrifices of those who served, the centenary of the armistice should prompt some reflection on the conflicts, consequences, and the dangers of rolling what Otto von Bismarck called the iron dice of war.