Mare Nostrum

Apollon Uni The Triton (prologue) (as Uni Apollon)

Álex Nova Don Esteban Ferragut (prologue) (as Alex Nova)

Kada-Abd-el-Kader Don Esteban's Son - Ulysses (prologue)

Hughie Mack Caragol (prologue)

Alice Terry Freya Talberg

Antonio Moreno Ulysses Ferragut

Mademoiselle Kithnou Ferragut's Wife - Dona Cinta (as Mle. Kithnou)

Mickey Brantford Ferragut's Son - Esteban (as Michael Brantford)

Rosita Ramírez Ferragut's Niece - Pepita

Frédéric Mariotti Toni - the Mate (as Fredrick Mariotti)

Madame Pâquerette Doctor Fedelmann (as Mme. Paquerette)

Fernand Mailly Count Kaledine

Andrews Engelmann Submarine Commander (as André von Engelman)

John George Servant (uncredited)