April 6, 2017 marked the 100th anniversary of the nation’s entry into World War I, a war that had engulfed most of Europe since 1914. The arrival of United States troops tipped the balance toward Allied victory, but this victory—which transformed the United States into a global power—also came at great cost.

Between 1914 and 1918, World War I claimed more than 17 million lives, including 116,516 United States troops, 53,402 of whom died in battle. More than 20 million people worldwide were wounded.

No state would sacrifice more for the war than New York. More than 500,000 New Yorkers served, comprising 12.5 percent of the four million United States troops; 13,956 lost their lives fighting for their country.

Once called the “War to End All Wars,” World War I was one of the bloodiest conflicts in human history and marked the dawn of devastating modernized weaponry such as poison gas, aerial bombing, machine guns, and long-range artillery.

New Yorkers from every corner of the state— farmers, factory workers, college boys, and tradesmen—answered the call to serve. For most of them, World War I was the first time they ventured more than 50 miles from their home towns.

Long before the United States entered the war, many New Yorkers volunteered for the Allied cause in France as aviators, nurses, and ambulance drivers. The first American aviator to die in the war, when his plane was shot down in June 1916, was New Yorker Victor Chapman, who had joined the all-American Lafayette Escadrille volunteer air corps.

In the fall of 1917, New York regiments began shipping overseas. Fighting alongside the Allies, these troops assailed the German hold of the Hindenburg Line, pushing them into retreat through several major engagements of the war, including the Aisne-Marne and the second Somme offensives, and the Battle of the Argonne Forest.

Among the New York regiments on the front lines were the 69th Infantry Regiment, known as the “Fighting 69th,” made up primarily of first- and second-generation Irish American immigrants, and the 369th Infantry Regiment, called the “Harlem Hellfighters,” the first African-American regiment to serve in combat in the war.

Twenty-five New Yorkers were awarded the Medal of Honor, the nation’s highest honor, for their valor.

New York provided more of the war’s supplies than any other state. Workers built planes on Long Island and in Buffalo; munitions across the state; and aerial cameras and lenses for gun sights at the Eastman Kodak Company in Rochester. At the Brooklyn Navy Yard, a crew of 18,000 built battleships and wooden submarine chasers, as well as sewed flags.

World War I witnessed the involvement of women in large numbers, and often in new roles. Women filled positions that were viewed as “men’s jobs” at shipyards, factories, and rail yards to boost war production. On the home front, New York suffragists organized women to sell war bonds, raise money for war relief, work in hospitals and on farms, and sew and knit items for the troops. Overseas, women served as Red Cross nurses and staffed Red Cross and YMCA comfort stations, offering combat-weary troops coffee, hot sandwiches, provisions, and a place to rest.

For the first time, American women also served in uniform in the armed services: as administrative yeomen in the U.S. Navy and Marine Corps; as nurses in the U.S. Army; and as bilingual telephone operators near the front, called “Hello Girls,” with the U.S. Army Signal Corps.

The war was felt acutely in every town, village, and city across New York State. Children wrote patriotic essays in school, sold war savings stamps, and gathered metal for the government to melt into weapons and tools. To conserve scarce resources for the troops, the government urged families to observe “Meatless Mondays,” “Wheatless Wednesdays,” and “Lightless nights.”

Letters from the front were a treasured lifeline for families and friends back home, and hometown newspapers often printed those shared by families. “Somewhere in France” was the common return address.

Though letters passed through military censors, troops were able to share vivid accounts of their lives as soldiers: long marches with fifty pounds of gear on their backs, descriptions of the French countryside and war-ravaged towns, and even the French’s bemused curiosity at the troops’ preference for cold milk. Troops also wrote about their first experience “over the top,” charging out of their trench and into combat in No Man’s Land.

For the families, the most important news was conveyed in a letter’s first line: that its author was safe and still alive.

After the signing of the Armistice, on November 11, 1918, New Yorkers cheered as newly returned troops marched in procession, some with the aid of crutches, down Fifth Avenue or Main Streets across the state.