Throughout armistice the Allies maintained the naval blockade of Germany that had begun during the war. As Germany was dependent on imports, it is estimated that 750,000 civilians had lost their lives during the war, and more died from starvation afterwards.
The continuation of the blockade after the fighting ended, as Robert Leckie wrote in Delivered From Evil, did much to "torment the Germans… driving them with the fury of despair into the arms of the devil." Terms of the Armistice did allow food to be shipped into Germany, but Allies required that Germany provide the ships. The German government was required to use its gold reserves, being unable to secure a loan from the United States (). Some historians have argued that the slow food shipments in early 1919 was one of the primary causes of World War II; others have advocated the Allies should have been even harder on Germany.
The blockade was not lifted until late June 1919 when the Treaty of Versailles was signed by most of the combatant nations.
There were some general consequences from the creation of a large number of new small states in eastern Europe. Internally these states tended to have substantial ethnic minorities, who looked to a neighbouring state where their ethnicity dominated the state. For example Czechoslovakia had Germans, Poles, Ruthenians and Ukrainians, Slovaks and Hungarians. Minority Treaties expressed an, albeit inadequate, attempt to deal with this problem. One consequence of the massive redrawing of borders and the political changes in the aftermath of war was the large number of European refugees. This led to the creation of the Nansen passport.
Ethnic minorities made the location of the frontiers generally unstable. Where the frontiers have remain unchanged, since 1918, there has often been the expulsion of an ethnic group, such as the Sudeten Germans. Economic and military cooperation amongst these small states was minimal ensuring that the defeated powers of Germany and the Soviet Union retained a latent capacity to dominate the region. In the immediate aftermath of the war, defeat drove cooperation between Germany and the Soviet Union but ultimately these two powers would compete to dominate eastern Europe.
Perhaps the single most important event precipitated by the privations of World War I was the Russian Revolution of 1917. A socialist and often explicitly Communist revolutionary wave occurred in many other European countries from 1917 onwards, notably in Germany and Hungary.
As a result of the Russian Provisional Governments' failure to cede territory, German and Austrian forces defeated the Russian armies, and the new communist government signed the Treaty of Brest-Litovsk in March 1918. In that treaty, Russia renounced all claims to Estonia, Finland, Latvia, Lithuania, Poland (specifically, the formerly Russian-controlled Congress Poland of 1815) and Ukraine, and it was left to Germany and Austria-Hungary "to determine the future status of these territories in agreement with their population." Later on, Lenin's government renounced also the Partition of Poland treaty, making it possible for Poland to claim its 1772 borders. However, the Treaty of Brest-Litovsk was rendered obsolete when Germany was defeated later in 1918, leaving the status of much of eastern Europe in an uncertain position.
During the Russian Revolution of 1917 and subsequent Russian Civil War, many non-Russian nations gained brief or longer lasting periods of independence. Finland, Lithuania, Latvia, and Estonia gained relatively permanent independence, although the Baltic states were annexed by the Soviet Union in 1940. Armenia, Georgia, and Azerbaijan were established as independent states in the Caucasus region. In 1922 these countries were invaded by Soviet forces, proclaimed as Soviet Republics, and eventually absorbed into the Soviet Union. However, Turkey had by then captured Armenian territory around Artvin, Kars, and Igdir: these territorial losses would become permanent. Romania was initially formed from the union of Wallachia and Moldova and later gained Bessarabia from Russia. After World War I, the Soviet Union was fortunate that Germany had lost the war as it was able to reject the Treaty of Brest-Litovsk.
The resolution of borders and governments in south-central Europe in the time after November 1918 was not easy. As the central government had ceased to operate in vast areas, these regions found themselves without a government and many new groups attempted to fill the void. During this same period, the population was facing food shortages and was, for the most part, demoralized by the losses incurred during the war. Various political parties, ranging from ardent nationalists, to social-democrats, to communists attempted to set up governments in the names of the different nationalities. In other areas, existing nation states such as Romania engaged regions that they considered to be theirs. These moves created de-facto governments that complicated life for diplomats, idealists, and the western allies.
The western allies were officially supposed to occupy the old Empire, but rarely had enough troops to do so effectively. They had to deal with local authorities who had their own agenda to fulfill. At the peace conference in Paris the diplomats had to reconcile these authorities with the competing demands of the nationalists who had turned to them for help during the war, the strategic or political desires of the Western allies themselves, and other agendas such as a desire to implement the spirit of the 14 points.
For example, in order to live up to the ideal of self determination laid out in the 14 points, Germans, whether Austrian or German, should be able to decide their own future and government. However, the French especially were concerned that an expanded Germany would be a huge security risk. Further complicating the situation, delegations such as the Czechs and Slovenians made strong claims on some German-speaking territories.
The result was treaties that compromised many ideals, offended many allies, and set up an entirely new order in the area. Many people hoped that the new nation states would allow for a new era of prosperity and peace in the region, free from the bitter quarrelling between nationalities that had marked the preceding fifty years. This hope proved far too optimistic. Changes in territorial configuration after World War I included:
The new states of eastern Europe nearly all had large national minorities. Millions of Germans found themselves in the newly created countries as minorities. One third of ethnic Hungarians found themselves living outside of Hungary. Many of these national minorities found themselves in bad situations because the modern governments were intent on defining the national character of the countries, often at the expense of the other nationalities.
The interwar years were hard for the Jews of the region. Most nationalists distrusted them because they were not fully integrated into 'national communities.' In contrast to times under the Austro-Hungarian monarchy, Jews were often ostracized and discriminated against. Although anti-semitism had been widespread during Habsburg rule, Jews faced no official discrimination because they were, for the most part, ardent supporters of the multi-national state and the monarchy. Jews had feared the rise of ardent nationalism and nation states, because they foresaw the difficulties that would arise.
The economic disruption of the war and the end of the Austro-Hungarian customs union created great hardship in many areas. Although many states were set up as democracies after the war, one by one, with the exception of Czechoslovakia, they reverted to some form of authoritarian rule. Many quarreled amongst themselves but were too weak to compete effectively. Later, when Germany rearmed, the nation states of south- central Europe were unable to resist its attacks, and fell under German domination to a much greater extent than had ever existed in Austria-Hungary.
At the end of the war, the Allies occupied Istanbul and the Ottoman government collapsed. The Treaty of Sèvres, a plan designed by the Allies to dismember the remaining Ottoman territories, was signed on August 10, 1920 though never ratified by the Sultan.
The occupation of Izmir by Greece on May 19, 1919 triggered a nationalist movement to rescind the terms of the treaty. Turkish revolutionaries led by Mustafa Kemal Atatürk, a successful Ottoman commander, rejected the terms enforced at Sèvres and under the guise of General Inspector of the Ottoman Army, left Istanbul for Samsun to organise the remaining Ottoman forces to resist the terms of the treaty. On the eastern front, the defeat of the Armenian forces in the Turkish-Armenian War and signing of the Treaty of Kars with the Soviet Union recovered territory lost to Armenia and Imperial Russia.
On the western front, the growing strength of the Turkish nationalist forces led Greece, with the backing of Britain, to invade deep into Anatolia in an attempt to deal a blow to the revolutionaries. At the Battle of Sakarya, the Greek army was defeated and forced into retreat, leading to the recovery of Izmir and withdrawal of Greece from Asia Minor. With the nationalists empowered, the army marched on to reclaim Istanbul, resulting in the Chanak crisis in which the British Prime Minister, David Lloyd George, was forced to resign. After Turkish resistance gained control over Anatolia and Istanbul, the Sèvres treaty was superseded by the Treaty of Lausanne which formally ended all hostilities and led to the creation of the modern Turkish republic. As a result, Turkey became the only power of World War I to overturn the terms of its defeat, and negotiate with the Allies as an equal.
The Lausanne treaty formally acknowledged the new League of Nations mandates in the Middle East, the cession of their territories on the Arabian Peninsula, and British sovereignty over Cyprus. The League of Nations granted France mandates over Syria and Lebanon and granted the United Kingdom mandates over Iraq and Palestine (which comprised two autonomous regions: Palestine and Transjordan). Parts of the Ottoman Empire on the Arabian Peninsula became part of what is today Saudi Arabia and Yemen. The dissolution of the Ottoman Empire became a pivotal milestone in the creation of the modern Middle East, the result of which bore witness to the creation of new conflicts and hostilities in the region.
British private investments abroad were sold, raising £550 million. However, £250 million new investment also took place during the war. The net financial loss was therefore approximately £300 million; less than two years investment compared to the pre-war average rate and more than replaced by 1928. Material loss was "slight": the most significant being 40% of the British merchant fleet sunk by German U-boats. Most of this was replaced in 1918 and all immediately after the war. The military historian Correlli Barnett has argued that "in objective truth the Great War in no way inflicted crippling economic damage on Britain" but that the war "crippled the British psychologically but in no other way".
Less concrete changes include the growing assertiveness of Commonwealth nations. Battles such as Gallipoli for Australia and New Zealand, and Vimy Ridge for Canada led to increased national pride and a greater reluctance to remain subordinate to Britain, leading to the growth of diplomatic autonomy in the 1920s. These battles were often decorated in propaganda in these nations as symbolic of their power during the war. Traditionally loyal dominions such as Newfoundland were deeply disillusioned by Britain's apparent disregard for their soldiers, eventually leading to the unification of Newfoundland into the Confederation of Canada. Colonies such as India and Nigeria also became increasingly assertive because of their participation in the war. The populations in these countries became increasingly aware of their own power and Britain's fragility.
In Ireland the delay in finding a resolution to the home rule issue, partly caused by the war, as well as the 1916 Easter Rising and a failed attempt to introduce conscription in Ireland, increased support for separatist radicals, and led indirectly to the outbreak of the Irish War of Independence in 1919.
France annexed the Independent Republic of Alsace-Lorraine, the country which had been established in the wake of Kaiser Wilhelm II's abdication, corresponding to the region which had been ceded to the German Empire during the 1870 Franco-Prussian War. At the 1919 Peace Conference, President Clemenceau's aim was to insure that Germany would not seek revenge in the following years. To this purpose, the chief commander of the Allied forces, Field Marshal Ferdinand Foch, had demanded that for the future protection of France the Rhine river should now form the border between France and Germany. Based on history, he was convinced that Germany would again become a threat, and, on hearing the terms of the Treaty of Versailles that had left Germany substantially intact, he observed with great accuracy that "This is not Peace. It is an Armistice for twenty years."
The destruction brought upon the French territory was to be indemnified by the reparations negotiated at Versailles. This financial imperative dominated France's foreign policy through-out the twenties, leading to the 1923 Occupation of the Ruhr in order to force Germany to pay. However, Germany was unable to pay, and obtained support from the United States. Thus, the Dawes Plan was negotiated after President Raymond Poincaré's occupation of the Ruhr, and then the Young Plan in 1929.
Also extremely important in the War was the participation of French colonial troops, including the Senegalese tirailleurs, from Indochina, North Africa, and Madagascar. When these soldiers returned to their homelands and continued to be treated as second class citizens, many became the nucleus of pro-independence groups.
Furthermore, under the state of war declared during the hostilities, the French economy had been somewhat centralized in order to be able to shift into a "war economy", leading to a first breach with classical liberalism.
Finally, the socialist's support of the National Union government (including Alexandre Millerand's nomination as Minister of War) marked a shift towards the SFIO's turn towards social-democracy and participation in "bourgeois governments", although Léon Blum maintained a socialist rhetoric.
Indeed, it should not have been difficult to see how, among the Allied Powers, Italy had been the one which benefited the most from the outcome of the war. Whereas Britain and France still faced a Germany which had kept about 80 percent of her industrial and economic potential and thus could attempt a revanche in a matter of years, Italy had definitively gotten rid of her century-old enemy: instead of the Austro-Hungarian Empire there were now a number of smaller states, none of which could pose a credible threat, and some of them could even fall within the Italian sphere of influence.
With the annexation of Friuli, Istria, Trentino-Alto Adige, Trieste, Zara and some Dalmatian islands, Italy had completed her territorial expansion and could now rely on secure borders. Furthermore, Italian sovereignty over Rhodes and the Dodecanese had been officially recognized, as well as the Italian special interests in Albania. However, a Yugoslavian state was created in order to limit Italian influence and expansion on the Balkans, and thus Italy was quite isolated. The Italian politicians failed to perceive the positive elements of the peace treaties and stressed the negative ones, and so the myth of the "mutilated victory" spread, fueling the Fascist propaganda and helping Mussolini seize power.
During the war, Italy had suffered fewer casualties than Britain and much fewer than France, and the social problems she was facing afterward (an inflated war industry to reconvert to civilian production, the large number of crippled people no longer able to sustain themselves, the new role of women) were common to other Allied countries which, however, did not suffer an authoritarian drift. The difference between Italy and the other western allies lies in the more arbitrated economic and social conditions, which made it more difficult for Italy to recover from similar difficulties. Due to similar reasons, most south and east European countries had to face political unrest, dictatorship and fascism in the period between the World Wars.
The real trauma for the British political class was the possibility of any future war. As early as 1923, Stanley Baldwin had recognised a new strategic reality that faced Britain in a disarmament speech Poison gas and the aerial bombing of civilians were new developments of the First World War. The British civilian population had not, for centuries, had any reason to fear invasion. So the new threat of poison gas dropped from enemy bombers excited a grossly exaggerated view of the civilian deaths that would occur on the outbreak of any war. Baldwin expressed this in his statement that The bomber will always get through. The traditional British policy of a balance of power in Europe no longer safeguarded the British home population. Out of this fear came appeasement. It is notable that neither Baldwin nor Neville Chamberlain had fought in the war but the anti-appeasers Antony Eden, Harold Macmillan and Winston Churchill had fought.
One gruesome reminder of the sacrifices of the generation was the fact that this was one of the first times in warfare whereby more men had died in battles than to disease, which had been the main cause of deaths in most previous wars. The Russo-Japanese War was the first war where battle deaths outnumbered disease deaths, but it had been fought on a much smaller scale between just two nations.
This social trauma made itself manifest in many different ways. Some people were revolted by nationalism and what it had caused; so, they began to work toward a more internationalist world through organizations such as the League of Nations. Pacifism became increasingly popular. Others had the opposite reaction, feeling that only military strength could be relied on for protection in a chaotic and inhumane world that did not respect hypothetical notions of civilization. Certainly a sense of disillusionment and cynicism became pronounced. Nihilism grew in popularity. Many people believed that the war heralded the end of the world as they had known it, including the collapse of capitalism and imperialism. Communist and socialist movements around the world drew strength from this theory, enjoying a level of popularity they had never known before. These feelings were most pronounced in areas directly or particularly harshly affected by the war, such as central Europe, Russia and France.
Artists such as Otto Dix, George Grosz, Ernst Barlach, and Käthe Kollwitz represented their experiences, or those of their society, in blunt paintings and sculpture. Similarly, authors such as Erich Maria Remarque wrote grim novels detailing their experiences. These works had a strong impact on society, causing a great deal of controversy and highlighting conflicting interpretations of the war. In Germany, nationalists including the Nazis believed that much of this work was degenerate and undermined the cohesion of society as well as dishonouring the dead.
Throughout the areas where trenches and fighting lines were located, such as the Champagne region of France, quantities of unexploded shells and other ammunition have remained, some of which remains dangerous, continuing to cause injuries and occasional fatalities in the 21st century. Some are found by farmers ploughing their fields and have been called the iron harvest. Some of this ammunition contains chemical toxic products such as mustard gas. Cleanup of major battlefields is a continuing task with no end in sight for decades more. Squads remove, defuse or destroy hundreds of tons of unexploded ammunition every year in Belgium and France.
The first major television documentary on the history of the war was the BBC's The Great War (1964), made in association with CBC (Canadian Broadcasting Corporation), the Australian Broadcasting Corporation and The Imperial War Museum. The series consists of 26 forty-minute episodes featuring extensive use of archive footage gathered from around the world and eyewitness interviews. Although some of the programme's conclusions have been disputed by historians it still makes compelling and often moving viewing.