Arnaud George Watson Massy (French pronunciation: [aʁno masi]; 6 July 1877 – 16 April 1950) was one of France's most successful professional golfers, most notable for winning the 1907 Open Championship.

The son of a sheep farmer, he worked on a sardine boat and supplemented his income by caddying at the new Biarritz golf course where a great many of the best professional golfers from Britain came to practice during the off-season in the warm climate of southern France.

Blessed with natural abilities, he learned from these pro golfers and in 1898 traveled to North Berwick, Scotland to develop his skills for a professional career.

[1] His victory raised the profile of the game in his native France, and with three other major players, he put on exhibition matches in various European cities that contributed significantly to the increased popularity of golf on the continent.

Married to a British woman, Janet Henderson, originally from North Berwick, East Lothian, he lived in Edinburgh, Scotland, during the 1920s and early 1930s.