Charles Blair Macdonald (1855-1939), was the first U.S. Amateur Champion in 1895.  Macdonald had gone to study at St. Andrews University in 1872 and took up golf, playing with the legends of the game.  When he returned to the States, he spread the gospel, and has had a lasting influence on the game.  He was instrumental in founding the United States Golf Association, and later was also a golf course architect.  He designed Chicago Golf Club in Wheaton, Illinois in 1895 and five years later it hosted the U.S. Open won by Harry Vardon.  His book "Scotland's Gift: Golf," published in 1928, is a wonderful account of his early life and ideas on golf course architecture.  His National Golf Links of America in Southampton, New York, remains one of his classic designs, and is ranked in the top ten courses in the United States.

Note:  Macdonald's date of birth has been disputed, but he was born in 1855.  See Evangelist of Golf  by George Bahto (2002).