He was a direct descendant of the 16th-century Venetian commander Marco Antonio Bragadin.
During World War II, Bragadin served as staff officer at Supermarina, the command of the Royal Italian Navy.
After the war he became a naval historian; besides dealing with specialist topics, in 1949 he wrote the educational work Che ha fatto la Marina?
1940–45) to make the navy's actions during World War II better known – they were then little known due to censorship.
He was also the advisor, screenwriter, production manager, consultant and assistant director on four 1950s Italian war films – three directed by Duilio Coletti (I sette dell'Orsa maggiore, Divisione Folgore and La grande speranza) and one by Antonio Leonviola (Siluri umani, 1954)