He was killed during the First World War while serving as a pilot, an event which inspired W. B. Yeats's poems "An Irish Airman Foresees His Death", "In Memory of Major Robert Gregory" and "Shepherd and Goatherd".
Han blev sedermera pilot och dödades under första världskriget, något som inspirerade Yeats att skriva dikterna "An Irish Airman Foresees His Death," "In Memory of Major Robert Gregory," och "Shepherd and Goatherd."