The London Naval Treaty, officially the Treaty for the Limitation and Reduction of Naval Armament, was an agreement between the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...
,
Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
,
France
France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...
,
Italy
Italy, officially the Italian Republic, is a country in Southern Europe, Southern and Western Europe, Western Europe. It consists of Italian Peninsula, a peninsula that extends into the Mediterranean Sea, with the Alps on its northern land b ...
, and the
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
that was signed on 22 April 1930. Seeking to address issues not covered in the 1922
Washington Naval Treaty
The Washington Naval Treaty, also known as the Five-Power Treaty, was signed during 1922 among the major Allies of World War I, Allies of World War I, which agreed to prevent an arms race by limiting Navy, naval construction. It was negotiated at ...
, which had created
tonnage
Tonnage is a measure of the capacity of a ship, and is commonly used to assess fees on commercial shipping. The term derives from the taxation paid on '' tuns'' or casks of wine. In modern maritime usage, "tonnage" specifically refers to a cal ...
limits for each nation's
surface warships, the new agreement regulated
submarine warfare
Submarine warfare is one of the four divisions of underwater warfare, the others being anti-submarine warfare, Naval mine, mine warfare and Naval mine, mine countermeasures.
Submarine warfare consists primarily of Diesel engine, diesel and nu ...
, further controlled cruisers and destroyers, and limited naval shipbuilding.
Ratifications were exchanged in London on 27 October 1930, and the treaty went into effect on the same day, but it was largely ineffective.
The treaty was registered in ''
League of Nations Treaty Series'' on 6 February 1931.
Conference

The signing of the treaty remains inextricably intertwined with the ongoing negotiations, which began before the official start of the London Naval Conference of 1930, evolved throughout the progress of the official conference schedule, and continued for years afterward.
Terms
The treaty was seen as an extension of the conditions agreed in the
Washington Naval Treaty
The Washington Naval Treaty, also known as the Five-Power Treaty, was signed during 1922 among the major Allies of World War I, Allies of World War I, which agreed to prevent an arms race by limiting Navy, naval construction. It was negotiated at ...
, an effort to prevent a naval
arms race
An arms race occurs when two or more groups compete in military superiority. It consists of a competition between two or more State (polity), states to have superior armed forces, concerning production of weapons, the growth of a military, and ...
after
World War I
World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...
.
The conference was a revival of the efforts that had gone into the 1927
Geneva Naval Conference at which the various negotiators had been unable to reach agreement because of bad feelings between the British and the American governments. The problem may have initially arisen from discussions held between US President President
Herbert Hoover
Herbert Clark Hoover (August 10, 1874 – October 20, 1964) was the 31st president of the United States, serving from 1929 to 1933. A wealthy mining engineer before his presidency, Hoover led the wartime Commission for Relief in Belgium and ...
and UK Prime Minister
Ramsay MacDonald
James Ramsay MacDonald (; 12 October 18669 November 1937) was a British statesman and politician who served as Prime Minister of the United Kingdom. The first two of his governments belonged to the Labour Party (UK), Labour Party, where he led ...
at
Rapidan Camp in 1929, but a range of factors affected tensions, which were exacerbated by the other nations at the conference.
Under the treaty, the
standard displacement of submarines was restricted to 2,000 tons, with each major power being allowed to keep three submarines of up to 2,800 tons except that France was allowed to keep one. The submarine gun caliber was also restricted for the first time to with one exception, an already-constructed French submarine being allowed to retain guns. That put an end to the 'big-gun' submarine concept pioneered by the British
M class and the French
''Surcouf''.
Per the terms of the treaty, Britain, the United States, and Japan reduced their number of capital ships, Japan by one, the United States by three, and Britain by five. Some were scrapped and others converted to auxiliary or training ships. All of these had been launched prior to WWI, and had smaller guns than most of the ships which were retained.
The treaty also established a distinction between cruisers armed with guns up to ("
light cruiser
A light cruiser is a type of small or medium-sized warship. The term is a shortening of the phrase "light armored cruiser", describing a small ship that carried armor in the same way as an armored cruiser: a protective belt and deck. Prior to thi ...
s" in unofficial parlance) from those with guns up to ("
heavy cruiser
A heavy cruiser was a type of cruiser, a naval warship designed for long range and high speed, armed generally with naval guns of roughly 203 mm (8 inches) in calibre, whose design parameters were dictated by the Washington Naval Treat ...
s"). The number of heavy cruisers was limited: Britain was permitted 15 with a total tonnage of 147,000, the Americans were permitted 18, totalling 180,000, and the Japanese were permitted 12, totalling 108,000 tons. For light cruisers, no numbers were specified but tonnage limits were 143,500 tons for the Americans, 192,200 tons for the British, and 100,450 tons for the Japanese.
Destroyer tonnage was also limited, with destroyers being defined as ships of less than 1,850 tons and guns up to . The Americans and the British were permitted up to 150,000 tons and Japan 105,500 tons.
Article 22 relating to submarine warfare declared
international law
International law, also known as public international law and the law of nations, is the set of Rule of law, rules, norms, Customary law, legal customs and standards that State (polity), states and other actors feel an obligation to, and generall ...
applied to them as to surface vessels. Also, merchant vessels that demonstrated "persistent refusal to stop" or "active resistance" could be sunk without the ship's crew and passengers being first delivered to a "place of safety."
Article 8 outlined smaller surface combatants. Ships between 600 and 2,000 tons, with guns not exceeding with a maximum of four gun mounts above without torpedo armament and up to , were exempt from tonnage limitations. The maximum specifications were designed around the French
Bougainville-class avisos, which were in construction at the time.
Warships under 600 tons were also completely exempt. That led to creative attempts to use the unlimited nature of the exemption with the Italian
Spica-class torpedo boats, Japanese
Chidori-class torpedo boats, French
La Melpomène-class torpedo boats and British
Kingfisher-class sloops.
Aftermath
The next phase of attempted naval arms control was the
Second Geneva Naval Conference in 1932. Active negotiations among the other treaty signatories continued during the following years.
"Naval Men See Hull on the London Talks; Admiral Leigh and Commander Wilkinson Will Sail Today to Act as Advisers"
''New York Times
''The New York Times'' (''NYT'') is an American daily newspaper based in New York City. ''The New York Times'' covers domestic, national, and international news, and publishes opinion pieces, investigative reports, and reviews. As one of ...
.'' 9 June 1934.
That was followed by the Second London Naval Treaty of 1936.
See also
* Treaty for the Limitation of Naval Armament
*Washington Naval Treaty
The Washington Naval Treaty, also known as the Five-Power Treaty, was signed during 1922 among the major Allies of World War I, Allies of World War I, which agreed to prevent an arms race by limiting Navy, naval construction. It was negotiated at ...
* Second London Naval Treaty – List of treaties signed in London.
* Treaty of London – List of treaties signed in London.
* May 15 Incident – attempted coup in Japan
Notes
Further reading
*
* Dingman, Roger. ''Power in the Pacific: The Origins of Naval Arms Limitation, 1914–1922'' (1976)
* Goldstein, Erik, and John H. Maurer, eds. ''The Washington Conference, 1921–22: Naval Rivalry, East Asian Stability and the Road to Pearl Harbor'' (Taylor & Francis, 1994).
* Maurer, John, and Christopher Bell, eds. ''At the Crossroads between Peace and War: The London Naval Conference in 1930'' (Naval Institute Press, 2014).
* Redford, Duncan. "Collective Security and Internal Dissent: The Navy League's Attempts to Develop a New Policy towards British Naval Power between 1919 and the 1922 Washington Naval Treaty." ''History'' 96.321 (2011): 48–67.
* Roskill, Stephen. ''Naval Policy Between Wars. Volume I: The Period of Anglo-American Antagonism 1919–1929'' (Seaforth Publishing, 2016).
* Steiner, Zara S. (2005)
''The Lights that Failed: European International History 1919–1933.''
Oxford: Oxford University Press
Oxford University Press (OUP) is the publishing house of the University of Oxford. It is the largest university press in the world. Its first book was printed in Oxford in 1478, with the Press officially granted the legal right to print books ...
.
OCLC 58853793
External links
Text of the treaty
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