York's Medal of Honor action occurred during the United States-led portion of the Meuse–Argonne offensive in France, which was intended to breach the Hindenburg line and force the Germans to surrender.

York was drafted during World War I; he initially claimed conscientious objector status on the grounds that his religious denomination forbade violence.

In October 1918, Private First Class (Acting Corporal) York was one of a group of seventeen soldiers assigned to infiltrate German lines and silence a machine gun position.

[5] Mary Elizabeth York was born in Pall Mall to William Brooks, who took his mother's maiden name as an alias of William H. Harrington after deserting from Company A of the 11th Michigan Cavalry Regiment during the American Civil War, and Nancy Pyle, and was the great-granddaughter of Conrad "Coonrod" Pyle, an English settler who settled Pall Mall, Tennessee.

William York and Mary Brooks married on December 25, 1881, and had eleven children: Henry Singleton, Joseph Marion, Alvin Cullum, Samuel John, Albert, Hattie, George Alexander, James Preston, Lillian Mae, Robert Daniel, and Lucy Erma.

In an October 8, 1918, attack that occurred during the Meuse–Argonne offensive, York's battalion aimed to capture German positions near Hill 223 (49°17′08″N 4°57′09″E / 49.28558°N 4.95242°E / 49.28558; 4.95242) along the Decauville railroad north of Chatel-Chéhéry, France.

Early's men were contending with the prisoners when German machine gun fire suddenly peppered the area, killing six Americans and wounding three others.

[21] Imperial German Army First Lieutenant Paul Jürgen Vollmer, commanding the 120th Reserve Infantry Regiment's 1st Battalion, emptied his pistol trying to kill York while he was contending with the machine guns.

York's actions silenced the German machine guns and were responsible for enabling the 328th Infantry to renew its attack to capture the Decauville Railroad.

York's explanation that God had been with him during the fight meshed neatly with the popular attitude that American involvement in the war was truly a holy crusade, and he returned to the United States in the spring of 1919 amid a tumultuous public welcome and a flood of business offers from people eager to capitalize on the soldier's reputation.

He had been home for barely a week when, on June 7, 1919, York and Gracie Loretta Williams were married by Tennessee Governor Albert H. Roberts in Pall Mall.

York concentrated on fund-raising, though he disappointed audiences who wanted to hear about the Argonne when he instead explained that "I occupied one space in a fifty mile front.

[41] At the time, U.S. public opinion was overwhelmingly in favor of the isolationist and non-interventionist approach, and York's unpopular views led to accusations that he was engaged in war-mongering.

Instead, he was commissioned as a major in the Army Signal Corps[42][44] and he toured training camps and participated in bond drives in support of the war effort, usually paying his own travel expenses.

Gen. Matthew Ridgway later recalled that York "created in the minds of farm boys and clerks ... the conviction that an aggressive soldier, well-trained and well-armed, can fight his way out of any situation."

[47] Biographer David Lee explored the reason Americans responded so favorably to his story: York's Appalachian heritage was central to his popularity because the media portrayed him as the archetypical mountain man.

At a time of domestic upheaval and international uncertainty, York's pioneer-like skill with a rifle, his homespun manner, and his fundamentalist piety endeared him to millions of Americans as a "contemporary ancestor" fresh from the backwoods of the southern mountains.

Ironically, while York endured as a symbol of an older America, he spent most of his adult life working to bring roads, schools, and industrial development to the mountains, changes that were destroying the society he had come to represent.

The resulting 1922 biography focused on York's Appalachian background, describing his upbringing among the "purest Anglo-Saxons to be found today", emphasizing popular stereotypes without bringing the man to life.

In a speech at the 1939 New York World's Fair, he said: We, the descendants of the pioneer long hunters of the mountains, have been called Scotch-Irish and pure Anglo-Saxon, and that is complimentary, I reckon.

Even today, I want you all to know, with all the clamor of the world and its evil attractions, you still find in the little humble log cabins in the Tennessee mountains that old-fashioned family altar of prayer—the same that they used to have in grandma's and grandpa's day—which is the true spirit of the long hunters.

[56] In 1941 the movie Sergeant York, directed by Howard Hawks with Gary Cooper in the title role, told about his life and Medal of Honor action.

[60] Some of the response to the film divided along political lines, with advocates of preparedness and aid to Great Britain enthusiastic ("Hollywood's first solid contribution to the national defense", said Time) and isolationists calling it "propaganda" for the administration.

[71] In the late 1940s he called for toughness in dealing with the Soviet Union and did not hesitate to recommend using the atomic bomb in a first strike, stating, "If they can't find anyone else to push the button, I will.

"[73] York and his wife Gracie had ten children, seven sons and three daughters, most named after American historical figures: an infant son (1920, died at 4 days), Alvin Cullum Jr. (1921–1983), George Edward Buxton (1923–2018), Woodrow Wilson (1925–1998), Samuel Huston (1928–1929), Andrew Jackson (1930–2022), Betsy Ross (born 1933), Mary Alice (1935–1991), Thomas Jefferson (1938–1972), and an infant daughter (1940, died the same day).

After a funeral service in his Jamestown church, with Gen. Matthew Ridgway representing President Lyndon Johnson,[80] York was buried at the Wolf River Cemetery in Pall Mall.

Later in life Gen. Lindsey would have a change of heart and support the other men's claims for recognition, which were again blocked by military officials citing a 1929 cutoff date for recommendation.

[95] Without the official support of the French government, Mastriano excavated the site and bulldozed the area in order to build two monuments and a historic trail.

[96] Mastriano's research has been strongly disputed by other historians who point out numerous errors in the history dissertation and subsequent book that he published on York.

Fullerton Laboratory for Spatial Technology at Middle Tennessee State University, placed the site 600 meters south of the location identified by Mastriano.