Effective Naval Diplomacy: German–Italian Submarine Cooperation in the Atlantic, 1939–41.

This article focuses on the role and impact of the Italian Navy’s submarine operations in the Battle of the Atlantic during World War II, highlighting the establishment and activities of the Command of the Atlantic Submarine Group (Betasom) in Bordeaux from September 1940 to September 1943. Despite structural and tactical limitations compared to German U-boats, Italian submarines sank 109 ships totaling nearly 594,000 tons, accounting for 5.9% of Axis successes in the Atlantic. The article emphasizes the importance of German–Italian naval diplomacy, joint training, and operational cooperation, which improved Italian effectiveness, particularly in the Central and South Atlantic where conditions suited their capabilities. While Italian contributions were peripheral relative to Germany’s, their presence complicated Allied shipping and demonstrated a rare example of effective Axis coalition warfare in the naval domain.