The history of the U.S. Public Health Service (PHS) provides a great overview why PHS officers wear uniforms, bear military ranks, and is one of eight uniformed services of the United States. The PHS was originally formed July 16, 1798, within the Treasury Department, by President John Adams which created the Marine Hospitals to prevent the spread of disease from returning sailors to the U.S. In 1870, the Marine Hospital Service became centralized under a supervising surgeon, known today as the Surgeon General. In 1871, the first supervising surgeon John Maynard Woodworth, a surgeon of the Union Army who served under General William Tecumseh Sherman, adopted a military model of a cadre of mobile uniformed career surgeons assigned to Marine Hospitals.

USPHS History