Helen Dore Boylston was a young American nurse serving on the front lines of World War I, so she was no stranger to chaos. But the steady drone of hundreds of motors advancing towards her hospital in France in 1918 was unlike anything she had ever heard before. An air raid was underway and the shells came “so low that her hair stood on end with every screech,” she’d write later, but this sound was something else.

When she looked to the horizon, she saw the source of the noise: illuminated only by the moonlight were an endless string of black ambulances, snaking as far as the eye could see. When the men they carried began arriving, their faces were ghost white and their wounds gaping and uncovered. Rows of them, blinded by their injuries, clung to each other to stay upright. Many of them, she noted, were mere teenagers.

It was going to be a long night but she wasn’t daunted. Boylston’s unit would go on to treat more casualties than any other group of American doctors and nurses. When the Great War ended later that year, claiming a staggering 40 million lives, Boylston—who had attained the rank of captain—was distraught.

“What are we all to do now? How can we go home to civilian life, to the never ending, never varying routine?” She wrote in her diary. “And the Twenty-second General Hospital, that vital living thing, saturated with the heights and depths of human emotion, will become a slowly fading memory of days when we really lived.”

Boylston was one of over nine million American women who joined the war effort. Not all of them faced the ravages of war firsthand—though many did, working as ambulance drivers who hurtled through artillery fire to rescue the wounded from the battlefield or to deliver emergency medical supplies to the front lines. Many women stayed home but worked in munitions factories or stitched surgical masks and gauze as Red Cross volunteers. Even librarians mobilized for war, building makeshift libraries in camps that would distribute nearly 10 million books and magazines to soldiers.

In total, the number of American women who joined the war effort dwarfed the nearly 5 million men who served in the armed forces.

Women of WWI
Lucile Patterson/The New York Historical Society/Getty Images
World War I poster in support of woman's service, 1917. ’ 

Women’s sudden entrance en masse into both the war and public life brought a central injustice of American life into sharp relief: though they fought and died in the war, they could not vote for it. This irony helped to crystallize the battle for the vote that suffragists had been fighting for almost 70 years.

“Who nurse the wounded, feed the sick, support the helpless, brave all danger? Who see their homes destroyed by shell and fire, their little ones made destitute, their daughters outraged?” read a sign by the Pennsylvania Women’s Suffrage Association. “Who dares say that war is not their business? In the name of Justice and Civilization give women a voice in Government and in the councils that make or prevent war.”

While there’s debate about how central World War I was to women achieving suffrage, President Woodrow Wilson himself would link the two, calling the women’s vote “vitally essential to the successful prosecution of the great war of humanity in which we are engaged.”

President Wilson Initially Opposed Women's Suffrage

In April of 1917, the United States entered the fray of the world’s first great conflict, declaring war against Germany. “The world must be made safe for democracy,” President Wilson told the American people, announcing his controversial decision. 

To many suffragists, this was a slap in the face. It had been decades since the fight for the vote had kicked off at the Seneca Falls Convention and while women had gotten the vote in several western states, the national fight had stagnated–in part because Wilson opposed it, believing the decision should be left up to individual states.

Women protesting the president’s opposition to suffrage had been picketing outside the White House every day for months by then, waving signs with messages like "Mr. President, How Long Must Women Wait For Liberty?" and "What Will You Do For Woman's Suffrage?"

But the country’s entrance into World War I gave a new impetus to their fight—one that the American public, and eventually the president himself, found hard to ignore.

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Women suffrage parade backing Woodrow Wilson's campaign for Woman's votes, 1916. 

A couple months after the first American troops arrived to Europe’s front lines, protester Virginia Arnold brandished a sign at George Washington University addressing President Woodrow Wilson as “Kaiser Wilson” and asking him if he had forgotten that his sympathy for Germans was because they were not self-governed when, in fact, “20,000,000 American women are not self-governed.”

Germany was being run as a military dictatorship at the time by Kaiser Wilhelm II, who enjoyed the title of “Supreme War Lord” and whose temper many blamed for the outbreak of the war. Needless to say, it wasn’t a favorable comparison.

Wilson would write to his daughter that the suffragists “seem bent on making their cause as obnoxious as possible.” Unfortunately for Wilson, it was also effective at a time when the majority of Americans were personally affected by the war and when the message of freedom served as powerful justification for its costs.

“Whoever denies that woman’s suffrage is not only an appropriate subject for discussion at this time, but an imperative war measure, is ignorant of the causes which led us into the war and the aims for which we are fighting in the war,” Carrie Chapman Catt would say the following year, adding that if this was truly a war for democracy and against autocracy, the United States could hardly continue to disenfranchise half its population by denying them the right to vote.

If the war’s symbolism wasn’t enough to sway public opinion in favor of suffrage, American women would soon offer another reason, the fact that they unquestionably carried a burden equal to, if not greater than, the men around them when it came to the war effort.

MPI/Getty Images
Women rivet heaters and passers on ship construction work in the Navy Yard in Seattle, Washington.

Millions of Women Participated in the War Effort

“Women were crucial to the process of mobilization of defense of the nation,” says Professor Lynn Duminel, the author of The Second Line of Defense: American Women and World War I, in a lecture on the topic.

Faced with a shortage of troops at the onset of war, Wilson ordered a draft for all men between 21 and 30 years old. Ten million men registered and 2.7 million were drafted. By the end of the war, over 4 million men had served in the Army, and 800,000 more had served in other military service branches. The millions of missing men left gaping holes in American industry at a time when the country couldn’t risk a hit to production.

Left without much choice, American women poured into the workforce. The change was sudden and staggering, dissolving the lines that once existed between where women did and didn’t belong.

On America’s railroads, for example, men held 98 percent of jobs. The women who were present worked behind the scenes in jobs like cleaning or catering. Once the war started, almost half of the railway workers of fighting age were recruited which meant that, almost overnight, the railroads became a decidedly female operation. Women were suddenly hyper-visible, doing everything from collecting tickets, to carrying luggage, to cleaning engines.

New jobs were also created because of the war–jobs that needed to be filled if America was to keep up with the pace of the war. Connecticut produced almost half of the country’s ammunition during the war and, from 1913 to 1917, the number of women working in factories in Connecticut increased by 105 percent because of increased demand and a decreased number of men.

A whopping 8 million women became Red Cross volunteers doing everything from sewing surgical dressings to working in canteens.

It wasn’t just men who went to war–many women also saw combat. The Red Cross trained 20,000 nurses to work, like Boylston, in the U.S. armed forces. Other women worked for the Salvation Army, darting in and out of the front lines offering coffee, doughnuts, and to write letters home to loved ones.

When the Navy came up short on recruits, women found a legal loophole that permitted them to enlist as yeoman, or non-commissioned officers, and work as everything from mechanics, to munitions workers, to translators.

David J. & Janice L. Frent/Corbis/Getty Images
Womens suffrage poster making strong appeal to voters to support candidates in favor of allowing women the right to vote. (Photo by David J. & Janice L. Frent/Corbis via Getty Images

Even for women who didn’t enter wage labor or go abroad, war permeated daily life. They were asked to sign a pledge committing to canning food, growing vegetables, and cutting out luxury items like meat and fats to help keep the country in fighting shape

Despite the trying and often violent circumstances, Boylston wasn’t alone in feeling empowered. “I think many women did find the war a genuinely liberating experience,” says historian Gail Braybon in a documentary about the war.

Photographs of women ploughing fields, working as carpenters, as machinists wearing overalls, even as war correspondents in trenches were circulated in newspapers and magazines around the world making their impact impossible to deny and turning the idea of what women were capable of on its head.

“Women were absolutely central to the process of fighting a global war,” adds Duminel. Suffragists, for their part, were determined not to let the country forget it.

It wasn’t just American women. In 1914, the German military equipment company Krupp had almost zero female employees; by 1917 they made up almost a third of their workforce. In 1914, Britain had 3.3 million women in wage labor and by 1917 that number had surged to 4.7 million.

World War I Bolstered Global Suffrage Movements

Women's massive participation in the war effort led, in part, to a wave of global suffrage in the wake of the war. Women got the right to vote in Canada in 1917, in Britain, Germany, and Poland in 1918, and in Austria and the Netherlands in 1919.

“The structures has fallen apart and created an opportunity for people to push for things they couldn’t push for before,” says Rebecca Mead, professor at Northern Michigan University. “It was a world war, it was a hugely disruptive influence.”

All of this, Americans suffragists believed, made their cause hard to refute. “The world expects America to be true to her ideals, to live up to the war aims she has set for herself. Woman suffrage is inevitable,” said Catt.

Despite the rhetoric at the time, there’s still debate amongst historians about how central the war was to American women finally getting the right to vote in 1920.

“It depreciates or obscures all of the hard work the women did decade after decade, continuing to persist even though they lost so many of these struggles,” says Mead of chalking women’s suffrage up to the war.

Change was also afoot before the war even started: Women were entering the workforce as early as 1910 and by the start of the war, women in 11 states already had the right to vote. Most of the professional gains women made during the war were also rescinded as soon as it ended. Men returned and wanted a return to normalcy, which meant taking their jobs back and returning women to the domestic lives they had left behind.

Still, that the war had an impact is irrefutable.

“We wouldn’t say the war explains it but the war allows us to look at it in very sharp ways,” says Duminel of women’s suffrage. “War is a marker of change.”

When President Wilson finally voiced his support for women’s right to vote on September 30, 1918, just over a month before the war ended, he reflected suffragists own language back to the country.

“We have made partners of the women in this war,” he said, “Shall we admit them only to a partnership of suffering and sacrifice and toil and not to a partnership of privilege?”

Though it would take another year for women to achieve suffrage–and decades more for women of color to be recognized–the war’s impact would endure and women’s lives would never really be the same.