Humanitarian Crisis: The war caused a humanitarian crisis, with widespread destruction, civilian casualties, and displacement of populations. Millions of people died from combat, disease, malnutrition, and the collapse of infrastructure.
War Crimes and Atrocities: World War I witnessed numerous war crimes and atrocities, including the use of chemical weapons, deliberate targeting of civilians, and the Armenian Genocide. These acts resulted in widespread condemnation and contributed to the negative legacy of the war.
Political Instability: The war led to the collapse of several empires, including the Ottoman Empire and the Austro-Hungarian Empire. It also contributed to the rise of nationalism, political extremism, and the Russian Revolution, which had profound geopolitical consequences in the decades that followed.
Economic Devastation: The war caused significant economic disruption and debt burdens for the participating nations. The costs of war production, military mobilization, and reconstruction were enormous, leaving many countries facing severe economic challenges in the postwar years.
Global Epidemics: The war facilitated the spread of diseases, including the influenza pandemic of 1918-1919, which killed an estimated 50-100 million people worldwide. The unsanitary conditions in trenches and the movement of troops contributed to the rapid transmission of the virus.