Treaty of San Francisco (サンフランシスコ講和条約 San-Furansisuko kōwa-Jōyaku), Peace Treaty with Japan (日本国との平和条約 Nihon-koku tono Heiwa-Jōyaku) 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 48 nations on September 8, 1951, at the War Memorial Opera House in San Francisco, California, United States.