[2][5] He grew up in Highlandtown, an East Baltimore neighborhood heavily influenced by German immigrants,[3][6] where his family belonged to Sacred Heart of Jesus Roman Catholic parish.

[5][7] Being of recent German-American heritage, Gunther did not automatically enlist in the armed forces as many others did soon after the United States declared war on Germany in April 1917.

Promoted as a supply sergeant, he was responsible for clothing in his military unit, and arrived in France in July 1918 as part of the incoming American Expeditionary Forces.

A critical letter home, in which he reported on the "miserable conditions" at the front and advised a friend to try anything to avoid being drafted, was intercepted by the Army postal censor.

[8] The Armistice with Germany was signed by 5:00 a.m., local time, but it would not come into force until 11:00 a.m. Gunther's squad approached a roadblock of two German machine guns in the village of Chaumont-devant-Damvillers near Meuse, in Lorraine.