World War I. The Great War. The War for Democracy. The War to End All Wars.

Despite what you may call it, the First World War brings to mind images of trenches sprawling over miles separated by desolate, inhospitable swaths of open ground (“no-man’s land”), gas mask-faced soldiers, primitive slow moving tanks, and double-decker planes engaging each other in early aerial combat. World War I was the first war to feature not only tanks and airplanes, but also poison gas, modern grenades, early submarines and the widespread use of machine guns.

Tomorrow marks 100 years since the guns of World War I fell silent. But while some hoped the devastation would be a wake-up call to humanity and usher in a lasting era of peace, the guns would not stay silent for long.

The war began with the assassination of Archduke Franz Ferdinand of Austria and his wife, Sophie, Duchess of Hohenberg, by Bosnian Serb Gavrilo Princip on June 28, 1914, in Sarajevo. It was the act that prompted Austria-Hungary to declare war on Serbia, which then caused their respective allies to join in on the fight.

Unbeknownst to Princip, his bullets had set into motion events that would change the world.

What followed was the most destructive war humanity had ever witnessed at that point. Battlefields like the Marne, the Somme, Ypres, Lys, Verdun, and their campaigns became synonymous with tremendous casualties, sometimes in the millions, all for little to no gain. After four long, bloody years, the Central Powers of Austria-Hungary, Germany and the Ottoman Empire surrendered to the Allied Powers of Great Britain, France and the United States, which fought in the war for only one year.

Despite the war staring in the wake of Archduke Ferdinand’s assassination, the Treaty of Versailles placed blame for the war on the shoulders of Germany. As part of the treaty terms, Germany was obligated to pay massive reparations, sending the country into an economic depression that made the German deutsche mark all but worthless. German politicians who supported the treaty were primarily socialists and communists, causing many to view them as enemies of the state. Rumors abounded that Jewish German citizens had not supported the war and had worked to sell out Germany to its enemies. These were some of the contributing factors that led to the rise of Adolf Hitler.

In the Far East, the war awakened a sense of military might among the Japanese. In 1905, Japan had defeated the Russians in the Russo-Japanese War (a victory that would help undermine the rule of Tsar Nicholas II), which cleared the way for Japan to annex the Korean Peninsula in 1910. During World War I, the Japanese successfully captured the German fortress of Tsingtao in China and seized German territories in the Marianas, Caroline, aand in China’s Shandong Province

In Russia, disastrous defeats against the Germans on the Eastern Front during World War I marked the end of the Romanov Dynasty. Tsar Nicholas II’s influence, already weakened by Russia’s defeat in the aforementioned Russo-Japanese War, became all the more weaker Russian troops went to the front lines to face heavy losses, sometimes without weapons or ammunition. In what was dubbed the “February Revolution” of 1917, Nicholas II abdicated the throne. In the ensuing “October Revolution” and Russian Civil War, the tsar and his family were executed and Vladimir Lenin was put in power, installing communist rule over Russia (the Soviet Union) that would last into the late 20th Century.

In the United States, a disillusioned population decided the best course of action would be to stay out of other nation’s affairs. The popular “America First” movement that came about after the war spurned this sense of isolationism.

These factors would serve as the perfect catalysts for a second, more devastating world war.

In Germany, Hitler promoted a nationalist movement that openly defied the Treaty of Versailles by rebuilding Germany’s military (a violation of the treaty’s terms) and reoccupying the Rhineland (which had been given to France under the treaty). In both cases, Great Britain and France, still with fresh memories of the overwhelming casualties and carnage from World War I, did nothing out of hopes to not provoke another war.

In March 1938, German forces marched unopposed into Austria. A vote held in April 1938 came back overwhelmingly in favor of Austria’s annexation (the Anschluss), prompting Hitler to then demand that Germany be given control of Czechoslovakia’s Sudetenland region, where many ethnic Germans lived. British and French leaders opted to appease Hitler by giving Germany the Sudetenland in the 1938 Munich Pact, which British Prime Minister Neville Chamberlain heralded as “peace in our time.” Under the terms, Hitler agreed there would be no further German expansion, only to break his promise by invading Czechoslovakia on March 15, 1939.

Again, Britain and France did nothing, but warned an invasion of Poland would prompt a military response. It was a promise they made good on when Germany invaded Poland on Sept. 1, 1939.

War had once again returned to the European continent.

But war had already come in Asia in 1931 when an emboldened Japanese military invaded Manchuria. In the ensuing Second Sino-Japanese War, Japan made significant gains into China. Japanese expansion also included numerous Pacific islands, including many British and Dutch colonies, as well as French Indochina (modern day Vietnam, Laos and Cambodia with parts of Thailand), Burma and India.

By 1941, the Soviet Union and the United States were involved. The end of the Second World War ushered in the nuclear age, with both nations emerging as world superpowers. With the capitalist United States and communist Soviet Union representing two different economic philosophies, the mutual mistrust turned into the Cold War. After China fell to communist forces in 1949, U.S. President Harry Trumanadopted a policy of containing the spread of communism, prompting wars in Korea, Vietnam, and the overthrow of governments in various Latin American nations.

The Cold War prompted the arms race and the space race, which, despite their original intentions, ended up yielding technological breakthroughs humanity had initially never thought possible.

In an attempt to keep further conflict in check, the United Nations was created, a successor to the ineffective League of Nations created after World War I. The U.N. created the nation of Israel for displaced European Jews that had survived the Holocaust, changing the course of history in the Middle East.

I could go on and on with other examples, but this column is long enough as it is. As the 20th Century progressed, and as the 21st Century continues to progress, virtually every event of global impact can and could in some way trace its origin back to the catalyst that was World War I.

And it all happened because Princip fired a few bullets.