William Henry Welch was an American physician, pathologist, bacteriologist, and medical school administrator. He was one of the "Big Four" founding professors at Johns Hopkins Hospital. He was the first dean of the Johns Hopkins University School of Medicine and was also the founder of the Johns Hopkins School of Hygiene and Public Health, the first school of public health in the country. The medical school library is named after Welch. In his lifetime he was referred to as "the Dean of American Medicine".