Millionaire Royal cocktail is the improved version from David Embury on the first Millionaire cocktail published by Harry MacElhone in 1923 ABC of Mixing Cocktails, where he notes to be a recipe from Ritz Hotel in London.

David Embury published the cocktail in his 1948 The Fine Art of Mixing Drinks. Helpfully he says: “in my opinion, it is improved by the addition of a small quantity of lemon juice. Two or three dashes of absinthe for each drink convert this cocktail into the Millionaire Royal.”