The Treaty of San Francisco comes into effect, restoring Japanese sovereignty and ending its state of war with most of the Allies of World War II.

The Treaty of San Francisco San-Furanshisuko, Peace Treaty with Japan or commonly known as the Treaty of Peace with Japan, Peace Treaty of San Francisco, or San Francisco Peace Treaty, mostly between Japan and the Allied Powers, was officially signed by 49 nations on September 8, 1951, in San Francisco, California. It came into force on April 28, 1952 and officially ended the American-led Allied Occupation of Japan. According to Article 11 of the Treaty, Japan accepts the judgments of the International Military Tribunal for the Far East and of other Allied War Crimes Courts imposed on Japan both within and outside Japan.

This treaty served to officially end Japan’s position as an imperial power, to allocate compensation to Allied civilians and former prisoners of war who had suffered Japanese war crimes during World War II, and to end the Allied post-war occupation of Japan and return sovereignty to that nation. This treaty made extensive use of the United Nations Charter and the Universal Declaration of Human Rights to enunciate the Allies’ goals.

This treaty, along with the Security Treaty signed that same day, is said to mark the beginning of the San Francisco System; this term, coined by historian John W. Dower, signifies the effects of Japan’s relationship with the United States and its role in the international arena as determined by these two treaties and is used to discuss the ways in which these effects have governed Japan’s post-war history.

This treaty also introduced the problem of the legal status of Taiwan due to its lack of specificity as to what country Taiwan was to be surrendered, and hence some supporters of Taiwan independence argue that sovereignty of Taiwan is still undetermined.