|American Field Service Director A. Piatt Andrew and Future Director Stephen Galatti|
The work of the American Field Service grew directly and organically out of the American Ambulance Hospital in Neuilly. Differences remained between those on its board who wished to concentrate on core hospital work and others who saw the practical value of a mobile service. (The "Ambulance" in the hospital title had the association in France more akin to that of a military hospital than an emergency vehicle.) But by late autumn 1914, its cars were allowed out into the field to serve regional hospitals.
The AFS became the largest of the volunteer ambulance services, expanding rapidly with the arrival at the turn of 1914/1915 of A. Piatt Andrew (1873-1936), a former assistant secretary of the U.S. Treasury, who was to become the AFS director. Andrew extended the scope of his operation and eventually separated completely from the Ambulance Hospital in 1916. He developed the role of all the different volunteer corps in the field by persuading the French authorities in April 1915 to allow the volunteers of the three American services to function immediately behind frontline trenches in battlefield areas.
As such, units of 25 to 30 men and some twenty ambulances were each assigned to individual French divisions, becoming the divisions’ principal ambulance service. Separate camion truck supply units were added, also manned by volunteers. They were to serve with the French across the Western Front and, in the case of two units of the AFS, with the French Army of the Orient in the Balkans.
A principal source of recruitment for the services came from American colleges, with east coast Ivy League institutions such as Harvard, Yale, Princeton, Dartmouth, and Cornell well represented plus west coast universities such as the University of California (Berkeley), and Stanford. The colleges alone contributed some 1,855 men to the American Field Service, aided in the U.S. by the recruitment efforts of Henry Sleeper (1878-1934), a friend of Piatt Andrew. AFS medical director Edmund Gros (1869-1942) also helped recruit AFS volunteers and others into the French legionnaire Lafayette Escadrille and Lafayette Flying Corps.