Dentice di Frasso was born on 22 January 1876 in San Vito dei Normanni, Kingdom of Italy.

He was a younger son of Senator Ernesto Dentice, 7th Prince of Frasso, and the former Countess Luisa Chotek von Chotkowa und Wognin (1840–1898).

[4] Among his extended family were aunts Donna Ippolita Emanuela Dentice di Frasso (wife of the Bavarian diplomat Count Count Otto von Bray-Steinburg),[5] and Donna Maria Dentice di Frasso (wife of Ferdinando Capece Minutolo, 1st Marquis of Bugnano).

[11] The restored the villa, which had been built for the Prime Minister of Italy Cardinal Giulio de' Medici in 1518, and, eventually, leased it to the Italian Ministry for Foreign Affairs, before it was purchased by Mussolini in 1941.

[15] On 29 June 1923, 47 year-old Dentice married another American heiress, the 35 year-old Dorothy Caldwell (née Taylor) Grahame-White at 280 Park Avenue in New York City (the home of Whitney Warren) in a wedding attended by Prince Gelasio Caetani, the Italian ambassador to the United States.