In what treaty did the U.S. agree to outlaw war?

In the Kellogg-Briand Pact, signed on August 27, 1928, the US., France, Great Britain, Japan, Italy, Belgium, Czechoslovakia, and Poland all agreed to give up war as an instrument of foreign policy.

However, the treaty lacked enforcement power, and within 14 years all the parties that signed it were fighting in World War II.

The pact named for President Calvin Coolidge’s Secretary of State Frank Kellogg and French foreign minister Aristide Briand.