The fall of Bordeaux to the Axis power, in the aftermath of French defeat in 1940, gave the Italians the opportunity to establish a naval base for submarines to attack Allied shipping in the Atlantic Ocean. Initially, BETASOM (an Italian acronym: “B” for Bordeaux is rendered with BETA and SOM is an abbreviation for “sommergibile”, which means submarine) consisted of dry docks, two basins connected by locks, and shore barracks. It could house up to thirty submarines. The base opened in August 1940 and by November, Italian submarines sunk an average of 200 gross tons per day (compared to a German rate of 1,115 gross tons per day). As the Italian crews gained more experience, their success rate improved dramatically (reaching 7,779 gross tons per day). Overall, the Italians sunk 109 Allied merchant ships totalling 601,425 tons for the loss of sixteen submarines.