In November 1914 it was only partially occupied when military authorities asked that it should be placed at their disposal. During the First World War, Alder Hey was used as a military hospital. The United States Army established Camp Hospital 40 on the site, operated by Hospital Unit Q and then by Unit W.
In January 1915 Major Robert Jones, the well-known orthopaedic specialist of Liverpool, was given special charge of a section of the hospital to concentrate on cases requiring orthopaedic treatment.
The majority of patients were not sent direct from the fighting at the front, but transferred from other hospitals, where there was every chance the patient would recover.
The hospital also had an occupational workshop, where disabled soldiers could learn new skills and possibly take up a skilled trade when they were discharged from the hospital. A link was created with the Old Swan Technical Institute and a workshop in Knotty Ash Village Hall, where a variety of classes were held from gardening to typewriting.
After the war, its role changed into that of a dedicated children’s hospital.