All Tennis Players How Many Grand Slams Has Willoughby Hamilton Won? Willoughby Hamilton (born as James Willoughby Hamilton; 9 December 1864 – 27 September 1943) was a co-world No. Read more on Wikipedia player.Willoughby Hamilton has won 1 Grand Slam. Facebook Twitter Email How Many Grand Slams Has Aryna Sabalenka Won? How Many Grand Slams Has Carlos Alcaraz Won? How Many Grand Slams Has Elena Rybakina Won?