|Full name||John Henry Derbyshire|
|National team||Great Britain|
|Born||28 November 1878|
|Died||25 November 1938 (aged 59)|
St Pancras, London, England
|Strokes||Freestyle, water polo|
|Club||Osborne Swimming Club|
John Henry "Rob" Derbyshire (29 November 1878 – 25 November 1938) was an English freestyle swimmer and water polo player from Chorlton, Lancashire, who competed in the 1900 Summer Olympics, 1906 Intercalated Games, 1908 Summer Olympics and 1912 Summer Olympics.
At the 1906 Intercalated Games in Athens he won a bronze medal as a member of British 4×250 metre freestyle relay team and also competed in the 100 metre freestyle and 400 metre freestyle events. Two years later at London he won a gold medal as a member of British 4×200 metre freestyle relay team and was second in his heat of 100 metre freestyle and did not advance. Four years later at Stockholm he was third in his heat of 100 metre freestyle and did not advance. The International Olympic Committee credits him with a gold medal in water polo at the 1900 Summer Olympics, but this is incorrect as sources contemporary to the Games indicate that he was in England too soon after the tournament to have been in Paris.
In 1921 Derbyshire was a founding member of the Penguin Swimming Club, later to become the Hammersmith Penguin Swimming Club through their merger with the Hammersmith Ladies Swimming Club (itself founded by his wife Alice in 1916) in 1976, which was renamed the West London Penguin Swimming and Water Polo Club in 2006. In 2005, he was posthumously inducted into the International Swimming Hall of Fame.