Born in Rome on 7 December 1911, Torlonia was the son of Marino Torlonia, 4th Prince di Civitella-Cesi and his American wife, Mary Elsie Moore.

[1][2] Don Alessandro's youngest sister was Donna Marina Torlonia di Civitella-Cesi,[1] grandmother of the American actress Brooke Shields.

[4][5] In 1941, when his mother was dying in New York City, Torlonia took a high speed boat from Portugal and was arrested in error by FBI, thinking he was an enemy of the state and taken to Ellis Island.

[6] In the 1980s, Torlonia held the title as the "richest man in Rome", as he was the heir to a banking fortune.

On 14 January 1935, Don Alessandro morganatically[8][9][10] married in Rome the Infanta Beatriz of Spain (1909–2002), a daughter of King Alfonso XIII of Spain and of Princess Victoria Eugenie of Battenberg.