A century ago, in the summer of 1914, a series of events set off an unprecedented global conflict that ultimately claimed the lives of more than 16 million people, dramatically redrew the maps of Europe, and set the stage for the 20th Century.
In 1914, the German Army sought a swift decisive victory over France, invading from the north. The plan failed, leading to a years-long bloody stalemate where millions of soldiers braved horrific conditions fighting for mere yards of territory.
Industrialization brought massive changes to warfare during the Great War. Newly-invented killing machines begat novel defense mechanisms, which, in turn spurred the development of even deadlier technologies. Nearly every aspect of what we would consider modern warfare debuted on World War I battlefields.
Animals were used in World War I on a scale never before seen—and never again repeated. Horses by the millions were put in service as cavalry mounts and beasts of burden, but they were not the only animals active in the war. Mules, dogs, camels, and pigeons all played vital roles, as well as many others—all at great risk, and with heavy cost.
World War I was the first major conflict to see widespread use of powered aircraft -- invented barely more than a decade before the fighting began. Airplanes, along with kites, tethered balloons, and zeppelins gave all major armies a new tactical platform to observe and attack enemy forces from above.
As countries caught up in the war sent soldiers to the front lines, they also built support behind the lines and at home, with women taking many roles. As villages became battlefields, refugees were scattered across Europe.
Moving troops and supplies by sea was vital to all armies involved in the war. The battle for control of the seas led to an arms race, new deadly tactics, and unprecedented loss of life at sea.
Centuries of colonialism had spread Europeans around the world, and 20th century developments in transportation were shrinking the globe. World War I pitted diverse nations and cultures against each other in a way no other conflict ever had.
Nearly four years of deadly stalemate on the Western Front slowly came to an end in 1918, as Allied armies pushed into Germany at enormous cost, leading the Central Powers to finally seek an armistice.
One hundred years after the start of the Great War, none of the participants remain alive, and we are left with aging relics, fading photographs, scarred landscapes being reclaimed by nature, and memorials and graveyards across the globe.