In the second half of the 1930s, Ministry of the Colonies of the Kingdom of Italy placed an order for four ships to transport bananas from Mogadishu in Italian Somaliland to Naples.

[2] According to legislative provision, these ships were constructed with the possibility of transforming them into auxiliary cruisers, so there was enough space left on deck to accommodate four 120 mm (4.7 in) cannons.

During the two years of peace Ramb II transported bananas from Italian Somaliland to Venice, Naples and Genoa, and carried various goods to Mogadishu on her return journeys.

During her short career as an auxiliary cruiser, Ramb II never ventured out and remained berthed in Massawa due to lack of allied merchant traffic and significant presence of Royal Navy in the Red Sea.

[3] On 27 February 1941 Ramb I was intercepted and sunk by cruiser HMNZS Leander, but the other two vessels sailed across the Indian Ocean and the Sunda Sea and safely arrived in Japan.

Ramb II then sailed to Tianjin, where she like other Italian merchant vessels was visited by Admiral Carlo Balsamo, a naval attache in Tokyo, who was inspecting ships available to carry natural rubber from the Far East to occupied France.

[1] She was officially chartered into the Imperial Japanese Navy as a stores ship in September 1942 and underwent additional refrigeration construction at Kawasaki Heavy Industries, Ltd.

After Italy signed Armistice of Cassibile on September 8, 1943, her Italian crew scuttled the ship at Kobe to prevent the vessel from falling into Japanese hands.

Calitea II was refloated by the Japanese, and on October 3, 1943 renamed Ikutagawa Maru and assigned call sign JXBY.

[4] Throughout 1944 the ship continued carrying supplies throughout the island ports of South East Asia, such as Makassar, Surabaya, Ambon and others.

[4] On January 12, 1945, as part of "Operation Gratitude" designed to support the liberation of Luzon in the Philippines, US Navy airplanes of Task Force 38 launched massive air strikes on ports, airfields and other military installations of Indochina, mainly located in and around Saigon.