[3] In 1917, Johnson returned to Athens to enlist in the United States Army and was sent to officer's training school at Fort McPherson in Atlanta, where on August 15, 1917, he was commissioned a major.

[2] During the Meuse-Argonne Offensive, Major Johnson was severely wounded, gassed, and he received a bad case of shell shock, which left him deaf in one ear.

Released from the hospital after the Armistice, he was reassigned to Headquarters, 112th Infantry, 56th Brigade, 28th Division, IV Army Corps, AEF.

While serving as assistant inspector general in the American Army of Occupation, based near Cochem, Germany, Johnson died of apoplexy.

[4][5] Although he was immediately buried in Cochem, his body was later returned to the United States and he was re-interred in Arlington National Cemetery.