The day after Britain declared war on Germany 100 years ago next month, a York doctor asked if Bootham School could be used as a hospital.
Two days later, fifty beds were ready in the gymnasium and classrooms.
The Quaker school was one of many public buildings converted to help with efforts on the homefront during the Great War.
Now, a researcher from the city's boarding school is researching the building's role ahead of the beginning of World War One's hundredth anniversary.
“The authorities were worried that a naval battle in the North Sea was imminent, and that they would need space for large numbers of casualties," archivist Jenny Orwin explained.
"The Mount School was also asked to become a hospital. Many of the elementary schools, as well as St. Peter's and Archbishop Holgate's, had already been commandeered as barracks for soldiers, according to Bootham’s Governors’ committee minutes."
Records compiled by the headmaster's wife, Ellen Rowntree, explain how volunteers turned up to the school to clear cupboards and desks, and make way for the many beds needed to satisfy demand.
Notes found in Mrs Rowntree's diary said: "A continuous stream of motors brought medical extras, spare blankets, surgical furniture, county ladies, hard-worked officers and busy doctors to inspect and advise, and St. John Ambulance nurses, who made the beds, covered tables and desks with white oilcloth, set up charts, and arranged bandages and splints.
"The art room was transformed into an operating theatre.
"Gas was brought in through the window and well-protected sterilises set up on the platform.
"Powerful lights were focused over the operating-table in the centre, and in a corner stood a large sink with taps."
The Bootham School archive has a mine of information about the war and the conflicting views of national support and Quaker pacifism.
At one point the headmaster Arthur Rowntree was suspected to be a German spy, but in August 1914 the school stood ready to help the wounded, just as in succeeding years many of its students would take on the care of the injured in battle through the Friends Ambulance Unit, while others took up arms following their conscience in a different direction.