[1] Between 1911 and 1912, as a midshipman, he first took part in a campaign in the Red Sea and Indian Ocean aboard the aviso Staffetta, and then fought in the Italo-Turkish war.

[1] From 1932 to 1934, after promotion to captain, he was sent to Washington as naval attaché and then, back in Italy, he became honorary aide-de-camp to Victor Emmanuel III.

[1] He was then placed in command of the 2nd Naval Division, formed by light cruisers Giovanni delle Bande Nere (flagship) and Bartolomeo Colleoni, and he still held this role when Italy entered World War II, on 10 June 1940.

[1] Since August 1941, having left the command of the Seventh Division, Casardi was for two years the staff and general services director of the Regia Marina.

[1][3] On September 11 Casardi, in order to avoid capture, sought refuge with his main collaborators in a building owned by his chief of staff, where he continued to work clandestinely until September 30, when German troops left Naples in the face of the insurrection of the population of the city and the Allied advance.