75 of the War Department in May 1917 and was headquartered in Allentown, Pennsylvania.

It incorporated the volunteer sections of the American Field Service, which was formed prior to the American entry into World War I, and provided medical services to injured French, British, and Italian soldiers during World War I.

[1] In World War II, the unit aided the British and the Italians.

[2] It was organized into 160 sections, each called Sanitary Squad Units.

The Sanitary Squad Unit typically supported a division, or about 10,000 soldiers.