Generally taken to have been invented under this name in 1921 by Malachy “Pat” McGarry, the first barman of the American Bar in Buck's Club. McGarry, formerly of the Irish Guards, was succeeded by his nephew Pat Shanley, also an Irish Guardsman, who went on serving for forty years. Buck's is a London gentleman's club founded in 1919 by Captain Herbert Buckmaster, sometime husband of the actress Dame Gladys Cooper. PG Wodehouse may well have modelled his fictional Drones Club after Buck's, even naming his club's barman "McGarry".
While the name certainly originates at Buck's, the wine-and-champagne mix is not unique, being known from French cocktails such as the 'Mimosa'. The true Buck's Club version is said to have an additional, undisclosed, ingredient, which is possibly a dash of Grenadine, or possibly not.

Buck's Club

The singing group 'Bucks Fizz', named after the drink
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