San Francisco Peace Treaty Day

What Is San Francisco Peace Treaty Day?

Every April 28th is also "San Francisco Peace Treaty Day" (サンフランシスコ講和記念日, San Furanshisuko Kōwa Kinenbi) in Japan. On April 28, 1952, the San Francisco Peace Treaty (サンフランシスコ平和条約) came into force — officially ending Japan's state of war with 48 Allied nations, restoring Japan's full sovereignty, and terminating the Allied Occupation of Japan that had governed the country since September 1945. The treaty's entry into force marked Japan's return to independence after nearly seven years of Occupation.

The San Francisco Peace Treaty

The San Francisco Peace Treaty was signed on September 8, 1951 by Japan and 48 nations at the San Francisco War Memorial Opera House, in a ceremony attended by John Foster Dulles (as the U.S. representative) and Japanese Prime Minister Yoshida Shigeru. The treaty formally ended WWII for the signatory nations, restored Japan's territorial sovereignty (with specified exceptions including Okinawa, which remained under U.S. administration until 1972), and required Japan to renounce territorial claims including Taiwan, Korea, the Kurils, and other territories. The Soviet Union, Poland, and Czechoslovakia were present but refused to sign; China was not invited.

Simultaneous Security Treaty

On the same day as the Peace Treaty was signed (September 8, 1951), Japan and the United States also signed the U.S.-Japan Security Treaty — allowing U.S. military forces to remain in Japan after the Occupation ended, providing for Japan's external defense while Japan rebuilt under its Article 9 war-renouncing constitution. The "1+1" structure of peace treaty and security treaty together defined the framework for U.S.-Japan relations that continues to this day.

"Day of Humiliation" Controversy

Some Japanese — particularly in Okinawa, which remained under U.S. administration while mainland Japan regained sovereignty — refer to April 28th as a "Day of Humiliation" (屈辱の日). Okinawa's continued exclusion from Japanese sovereignty on the day Japan regained independence is a source of particular grievance for Okinawans who felt abandoned by the mainland's peace settlement.

Fun Facts

• Yoshida's defiance: Prime Minister Yoshida Shigeru's decision to sign the peace treaty over opposition from both left (who wanted a neutral Japan) and right (who objected to the territorial concessions) reflected his pragmatic judgment that Japan's economic recovery required American partnership even at the cost of the full independence he sought.
• Treaty parties: The San Francisco Peace Treaty's unusual composition — signed by 48 nations but not the Soviet Union or China — left legal ambiguities about Japan's formal peace relationships with these powers that required separate subsequent negotiations (Soviet-Japanese Joint Declaration, 1956; China-Japan Peace and Friendship Treaty, 1978).