During World War II, the top floor of Mater Children’s Hospital was vacated and prepared to receive soldiers, and all three hospitals blacked out their windows with paper. Blast-proof walls were also erected.
The stained glass windows in the Mater Convent Chapel were removed and stored safely, and sandbags were positioned around all buildings. Air-raid shelters were also erected behind Mater Private Hospital.
Mater and the Brisbane General Hospital both became collection centres to support World War II. Blood collected at Mater was flown to Papua New Guinea during the night and administered to wounded military personnel.
At the end of the war, repatriated prisoners of war from Japanese prison camps arrived at Mater for care.