He served on the battleships Vittorio Emanuele and Benedetto Brin, before joining the naval air arm just before World War I.

When Italy entered World War II on 10 June 1940, Courten first commanded from August 1941 to March 1942 the 7th Division, in which he participated in the First Battle of Sirte.

When the Armistice of Cassibile — under which Italy made peace with the Allies and switched sides in the war — was announced on 8 September 1943, he convinced the fleet commander.

On 23 September 1943 Courten and Admiral Andrew Cunningham met at Taranto and reached the so-called Gentlemen's Agreement, which defined the collaboration of the Regia Marina with the Allies.

He remained Minister of the Navy until July 1946 and Chief of Staff until December 1946, when he resigned to protest the clauses of the Paris Peace Treaties.