"Gladio" was laid down at Cantieri Riuniti dell'Adriatico (CRDA)'s Trieste shipyard on 9 January 1943 and was launched on 15 June that year. On 8 September 1943, an Armistice between Italy and the Allies was announced, and in response, German forces carried out pre-planned operations to disarm Italian forces, which resulted in ships under construction, like "Gladio", being seized and completed by the Germans. "Gladio" was completed by the Germans as "TA37" on 8 January 1944.