The ship was laid down in 1913 at Sir James Laing & Sons Ltd. shipyard at Deptford, launched on November 14, 1913 (yard number 644), and commissioned on December 20 of the same year.

The tanker made regular trips from Tampico and Tuxpan on the Gulf Coast of Mexico to the same Chilean ports through early 1922.

San Joaquin was acquired in June 1929 by a Norwegian whaling company A/S Hektor (operated by Nils Bugge) and renamed Melville.

Melville also transported members, equipment and aircraft of Sir George Hubert Wilkins's expedition in late 1929 on their way to the South Shetland Islands.

However, Metaxas saw the war as a great opportunity of making money and rearming Greek Armed Forces by selling ammunition and weapons to both parties of the conflict.

[14] As a result, most Greek ships travelling in the Western Mediterranean were considered by Spanish Nationalists, as well as their German and Italian allies, as enemies.

On 1 September 1937, Iolcos which was just recently renamed Woodford and in the process of being transferred to the British registry, was on her journey from Constanta to Valencia with a full load of fuel oil.

[17] Even though the ship was travelling under the British flag, the captain of the submarine, Giuseppe Mellina, believed the tanker was using a false name Woodford, as the crew appeared to be Romanian.