World War I marked the first war in which American women were allowed to enlist in the armed forces. While thousands of women did join branches of the army in an official capacity, receiving veterans status and benefits after the war's close, the majority of female involvement was done through voluntary organizations of the war effort or through becoming a nurse for the military. Additionally, women made an impact on the war indirectly by filling the workforce, becoming employed in the jobs left behind by male soldiers.
U.S. Navy, Marine Corps, and Coast Guard
More than 1,476 U.S. Navy nurses (American military nurses were all women then) served in military hospitals stateside and overseas. Over 400 U.S. military nurses died in service, almost all from the Spanish flu epidemic which swept through crowded military camps, hospitals, and ports of embarkation.
The first American women enlisted into the regular armed forces were 13,500 women admitted into active duty in the U.S. Navy. They served stateside in jobs and received the same benefits and responsibilities as men, including identical pay (US$28.75 per month), and were treated as veterans after the war.
The U.S. Marine Corps enlisted 305 female Marine Reservists (F) to "free men to fight" by filling positions such as clerks and telephone operators on the home front.
During World War I, Myrtle Hazard enlisted in the Coast Guard, served as a telegraph operator, and was discharged as an Electrician 1st Class. She was the only woman to serve in the Coast Guard during the war and she is the namesake of USCGC Myrtle Hazard. Wartime newspapers erroneously reported that twin sisters Genevieve and Lucille Baker were the first women to serve in the Coast Guard. While they tried to enlist, they were not accepted.
These women were demobilized when hostilities ceased, and aside from the Nurse Corps, the uniformed military once again became exclusively male. In 1942, women were brought into the military again, largely following the British model.
U.S. Army
During the course of the war, 21,498 U.S. Army nurses (American military nurses were all women then) served in military hospitals in the United States and overseas. Many of these women were positioned near to battlefields, and they tended to over a million soldiers who had been wounded or were unwell. 272 U.S. Army nurses died of disease (mainly tuberculosis, influenza, and pneumonia). Eighteen African-American Army nurses served stateside caring for German prisoners of war (POWs) and African-American soldiers. They were assigned to Camp Grant, IL, and Camp Sherman, OH, and lived in segregated quarters.
Hello Girls was the colloquial name for American female switchboard operators in World War I, formally known as the Signal Corps Female Telephone Operators Unit. During World War I, these switchboard operators were sworn into the Army Signal Corps. This corps was formed in 1917 from a call by General John J. Pershing to improve the worsening state of communications on the Western front. Applicants for the Signal Corps Female Telephone Operators Unit had to be bilingual in English and French to ensure that orders would be heard by anyone. Over 7,000 women applied, but only 450 women were accepted. Many of these women were former switchboard operators or employees at telecommunications companies. Despite the fact that they wore Army Uniforms and were subject to Army Regulations (and Chief Operator Grace Banker received the Distinguished Service Medal), they were not given honorable discharges but were considered "civilians" employed by the military, because Army Regulations specified the male gender. Not until 1978, the 60th anniversary of the end of World War I, did Congress approve veteran status and honorable discharges for the surviving women who had served in the Signal Corps Female Telephone Operators Unit.