Herbert Johnson Louis was born on April 22, 1928, in Evanston, Illinois, the son of Henrietta Johnson Louis and John Jeffry Louis, and the great grandson of the S. C. Johnson & Son company founder Samuel Curtis Johnson, Sr.. He was educated at Deerfield Academy, and Northwestern University Medical School in Chicago. He served in the United States Army His brother John J. Louis, Jr. (1925–1995), was the US Ambassador to the United Kingdom.