The London Naval Treaty is one that went in to effect and was ratified in October 27, 1930. It was not registered in to the League of Nation Treaties Series until February 6, 1931. The treaty was an agreement entered in to by the: US, UK, Japan, France, and Italy, which was in place to regulate naval shipbuilding and submarine warfare.

Background

The London Naval Treaty was initially discussed at the Geneva Naval Conference in 1927, but because of tensions between President Hoover (US) and Prime Minister MacDonald (UK), nothing was ratified, and the treaty was never entered nor put in to effect because of disagreements. There were tensions dating from discussions held at Raiden Camp in 1929, along with other factors and issues between the two leaders and countries.

Terms

Some of the important terms in the treaty included:
» Restrictions of standard displacement and gun calibers on submarine ships, putting ends to the “big-gun” submarine which UK and France had set out to battles.
» Cruisers with arms smaller than 6.1” were differentiated between those armed with 8” calibers, were distinguished as light or heavy cruisers.
» The number of heavy cruisers a country could have was limited: US (18), UK (15), and Japan (12).
» The light cruisers had no limit, but the amount of tons was limited to: US (143,500), UK (192,200), and Japan (100,450).
» Article 22 of the treaty also specified that International Law was the leading governing body for these vessels; and, rules were set forth that if merchant vessels were persistent and refused to stop (when informed to), these ships could be sunk, even if passengers and cargo were on board.

Second Convention

In 1932, the second phase of the London Naval Treaty was discussed at the Second Geneva Naval Conference. Italy had retired several ships, totaling 130,000 tons of naval vessels during that year. The remaining countries to the convention continued discussions, and in March 25, 1936, the Second London Naval Treaty was signed.