20, located in Châtel-Guyon, France, was one of the hundreds of Base Hospitals created to treat soldiers wounded during the First World War.

While the United States had not yet formally joined the First World War, many were anticipating its inevitable entry.

The University of Pennsylvania, in conjunction with the American Red Cross and the War Department, began organizing Base Hospital No.

Penn Medical School Professor, Lt. Col. John B. Carnett, was put in charge of organizing the Surgical Operating Team No.

[5] In addition, sixty-five nurses and 153 enlisted men volunteered to serve the hospital.

All personnel received at least five weeks hospital training as orderlies and anesthetists, as well as full instruction in practical first aid from Col. Eliason and were required to be able to apply splints, bandages, and dressings.

While the initial peacetime amount had been covered by a donation from the Harrison Fund, more would be required.

[6] With personnel trained and all the necessary funds and equipment, the whole operation left the University for Camp Merritt, New Jersey on 1 April 1918.

[6] During their three weeks in New Jersey, they were joined by the nurses, dietitians and three civilian stenographers, who had been stationed at Ellis Island, and finally on 22 April, they all set sail on the USS Leviathan.

[7] The hospital treated battle wounds, exposure to mustard, phosgene, and chlorine gas, as well as contagious and infectious diseases.

[9]In addition to regular duties, they were one of three hospitals designated for supervising suspected tuberculosis cases.

[9] The largest single number of patients to arrive in one day came on July 25 from the Battle of Château-Thierry (1918), 587 at the time.

[6][10] During their time in operation they received wounded soldiers from the St. Mihiel salient, Verdun, Argonne, and others.

[6] In the nine months that the hospital was operational, it received 8,703 patients, only 65 of whom died, plus the death of one staff member.

[11] Following the close of the hospital, the operation was dismantled and personnel were transferred or began to return home.

The majority of the personnel left on the USS Freedom, 13 April 1919 and formally demobilized at Camp Dix, 5 May 1919.

61 went to Toul for instruction in war surgery on 8 June 1918, before reporting for active duty July 21, at ARC Military Hospital No.

Towards the end of August, the unit relocated to St. Mihiel, and moved on to the Argonne front in late September and remained there throughout the rest of the war.

The team performed approximately 600 operations as well as dressing wounds and other medical procedures before returning to Châtel-Guyon.

[16] Departing from Châtel-Guyon on the 24th of September, the team arrived at Souilly, where they took over the Shock Ward of Evacuation Hospital No.

They held this post, working sometimes day and night, until November 26, before being relieved from duty and returning to Base Hospital No.