Washington Naval Treaty
Memorial Continental Hall, Washington, D.C., USA
What happened
The United States, the British Empire, Japan, France and Italy, at a conference led by US Secretary of State Charles Evans Hughes. After the First World War, the great powers were racing to build huge, costly battleships. At the Washington Naval Conference they agreed to limit the size of their navies by a fixed ratio. They also agreed to a ten-year pause in building battleships and to scrap many existing or planned ships.
Why it matters
Why it matters: It was an early arms-control treaty, aimed at preventing a naval arms race among the great powers. It showed that rival nations could agree to limit their weapons through talks.
What came next
The limits were extended in 1930 and 1936. Japan gave notice in 1934 that it would leave the treaty, and its limits ended in 1936.
Did you know?
American codebreakers secretly read Japan's messages during the conference, so the US knew the lowest terms Japan would accept.
Timeline
- November 1921The Washington Naval Conference opens.
- 6 February 1922The Washington Naval Treaty is signed.
- 1930The London Naval Treaty extends the limits.
- 29 December 1934Japan gives notice that it will leave the treaty.
- End of 1936The treaty's limits expire.