Washington Naval Treaty

The ***Washington Naval Treaty***, also known as the ***Five-Power Treaty***, was a treaty signed during 1922 among the major Allies of World War I, which agreed to prevent an arms race by limiting naval construction. It was negotiated at the Washington Naval Conference in Washington, D.C. from November 1921 to February 1922 and signed by the governments of the British Empire (including the United Kingdom, Canada, Australia, New Zealand, South Africa and India), United States of America, France, Italy, and Japan. It limited the construction of battleships, battlecruisers and aircraft carriers by the signatories. The numbers of other categories of warships, including cruisers, destroyers, and submarines, were not limited by the treaty, but those ships were limited to 10,000 tons displacement each.

The treaty was concluded on February 6, 1922. Ratifications of that treaty were exchanged in Washington on August 17, 1923, and it was registered in the League of Nations Treaty Series on April 16, 1924.

Later naval arms limitation conferences sought additional limitations of warship building. The terms of the Washington Naval Treaty were modified by the London Naval Treaty of 1930 and the Second London Naval Treaty of 1936. By the mid-1930s, Japan and Italy renounced the treaties, while Germany renounced the Treaty of Versailles which had limited its navy. Naval arms limitation became increasingly difficult for the other signatories.

## Terms

 United States of America
 Empire of Japan
 France
 Italy

The treaty strictly limited both the tonnage and construction of capital ships and aircraft carriers and included limits of the size of individual ships.

The qualitative limits of each type of ship were as follows:

* Capital ships (battleships and battlecruisers) were limited to 35,000 tons standard displacement and guns of no larger than 16-inch calibre. (Articles V and VI)

* Aircraft carriers were limited to 27,000 tons and could carry no more than 10 heavy guns, of a maximum calibre of 8 inches. However, each signatory was allowed to use two existing capital ship hulls for aircraft carriers, with a displacement limit of 33,000 tons each (Articles IX and X). For the purposes of the treaty, an aircraft carrier was defined as a warship displacing more than 10,000 tons constructed exclusively for launching and landing aircraft. Carriers lighter than 10,000 tons, therefore, did not count towards the tonnage limits (Article XX, part 4). Moreover, all aircraft carriers then in service or building (HMS Argus, HMS Eagle, HMS Furious, HMS Hermes, USS Langley and IJN Hōshō) were declared "experimental" and not counted (Article VIII).

* All other warships were limited to a maximum displacement of 10,000 tons and a maximum gun calibre of 8 inches (Articles XI and XII).

The treaty also detailed by Chapter II the individual ships to be retained by each navy, including the allowance for the United States to complete two further ships of the Colorado-class and a single Lexington class ship, for Japan to complete the IJN Mutsu and Amagi-class IJN Ashataki, and for the UK to complete three new ships in accordance with the treaty limits (these would become the Nelson-class).

Chapter II, part 2, detailed what was to be done to render a ship ineffective for military use. In addition to sinking or scrapping, a limited number of ships could be converted as target ships or training vessels if their armament, armour and other combat-essential parts were removed completely. Some could also be converted into aircraft carriers.
Part 3, Section II specified the ships to be scrapped to comply with the treaty and when the remaining ships could be replaced. In all, the United States had to scrap 29 existing or planned capital ships, Britain 23 and Japan 16.

## Legacy

The treaty marked the end of a long period of increases of battleship construction. Many ships that were being constructed were scrapped or converted into aircraft carriers. Treaty limits were respected and then extended by the London Naval Treaty of 1930. It was not until the mid-1930s that navies began to build battleships once again, and the power and the size of new battleships began to increase once again. The Second London Naval Treaty of 1936 sought to extend the Washington Treaty limits until 1942, but the absence of Japan or Italy made it largely ineffective.
There were fewer effects on cruiser building. The treaty specified 10,000 tons and 8-inch guns as the maximum size of a cruiser, but that was also the minimum size cruiser that any navy was willing to build. The treaty began a building competition of 8-inch, 10,000-ton "treaty cruisers", which gave further cause for concern. Subsequent naval treaties sought to address that by limiting cruiser, destroyer and submarine tonnage.

Unofficial effects of the treaty included the end of the Anglo-Japanese Alliance.
Although it was not part of the Washington Treaty in any way, the American delegates had made it clear that they would not agree to the treaty unless the British ended their alliance with the Japanese. The 1921 Imperial Conference earlier in the year had already decided not to renew the Alliance.

## Appearances

* *The Greatest Generation*  (first mentioned)

## Sources

* https://en.m.wikipedia.org/wiki/Washington\_Naval\_Treaty
* http://www.navweaps.com/index\_tech/tech-089\_Washington\_Naval\_Limitation\_Treaty\_1922.php