Over 80 per cent of Australian battle casualties in the First World War occurred on the Western Front. In order to deal with the thousands of wounded men, a system of battlefield evacuation and treatment was developed. Relays of stretcher-bearers would carry the wounded through the difficult terrain, often under shell-fire. It could take many hours for a wounded man to be transported back to the surgeons and nurses at the Casualty Clearing Stations (CCS).
During major battles, the number of casualties could overwhelm the evacuation system. Private Roger Morgan of the 2nd Battalion described the casualties at Pozières on 23 July 1916:
"dead and dying heroes lie one on top of the other, many groan in agony, others just lie still unconscious of all pain … for some time we have been unable to get room inside and have had to dress wounds out in the open on the roadside … Many of them were blown to pieces lying there in the open unable to move."