title: John S. Macdonald
text: # John S. Macdonald
  
  John S. Macdonald may refer to:
  
  * John Sandfield Macdonald, first Premier of Ontario
  * Harry Macdonough (John Scantlebury Macdonald), Canadian singer and recording executive of the early 20th century
  * John S. MacDonald, Canadian engineer and businessman
  * John Smyth Macdonald (1867–1941), British physiologist
  