The Washington Naval Conference of 1921-1922 was a major navel disarmament treaty done between the major naval powers. They wanted to essentially prevent another war/arms race just like WW1 and the British-German naval race.

At the time, America’s major naval competitors were Britain and Japan. However, a total of nine nations were invited. These include: Britain, Japan, France, Italy, Belgium, China, Portugal, Netherlands. America is the ninth country being the host. Three treaties came from this conference.

The Five-Power Treaty was signed by the US, Britain, Japan, France, and Italy. This is the most famous of the three. America and Britain were capped at 500,000 tons of displacement. Japan was at 300,000 tons and France and Italy were each at 175,000 tons. America and Britain were allowed higher tonnages due to their wide-reaching holdings. Not to mention, new capital ships were banned and older ships were encouraged to be scrapped.

The Four-Power Treaty was between Britain, France, America, and Japan. It essentially said they would reach out to each other in the event of a major crisis in the far east. This was also made to nullify the Anglo-Japanese treaty of 1902 as that would mean Britain and Japan could team up against America.

The Nine-Power Treaty was made between all of the powers listed above to respect the territories of China. It also made concessions such as stating that Manchuria was Japanese. China also agreed not to favor any one country for business. From this, the bilateral Shandong Treaty was made between China and Japan in which Japan handed back some territories and withdrew troops from Siberia. The Island of Yap was also allowed to be used by the US for its radio equipment.

Overall, the Treaty did good because it delayed a major war. That war, WW2, would eventually occur but it occurred after 20 years not 2.