An initial U.S. advance party flew into Atsugi Field near Tokyo to establish communications and begin implementing the Allied occupation framework that would be administered under SCAP/GHQ.
General Douglas MacArthur arrived (via Atsugi/Yokohama area) to assume duties as Supreme Commander for the Allied Powers (SCAP), becoming the central authority overseeing demilitarization and democratization policies.
Representatives of Japan and the Allied Powers signed the Japanese Instrument of Surrender aboard the USS Missouri in Tokyo Bay, formalizing the end of World War II hostilities and enabling occupation governance to proceed under Allied authority.
SCAP issued an initial directive aimed at breaking up Japan’s prewar economic concentration by ordering the dissolution of major holding companies associated with the large industrial-financial combines (zaibatsu).
Occupation authorities pressed for agrarian restructuring; Japan adopted 1946 land-reform legislation (including the Special Measure for the Establishment of Owner-Farmers and related adjustments), which became the legal foundation for large-scale transfer of land from landlords to tenant cultivators.
SCAP ordered the Japanese government to remove and exclude “undesirable” personnel—especially those associated with militarism and ultranationalist organizations—from public office, reshaping political and administrative leadership during the occupation.
After Government Section drafting inside GHQ, the completed GHQ draft constitution was delivered to the Japanese government, setting the basis for Japan’s postwar constitutional settlement (including the renunciation of war in Article 9).
Japan held its first postwar general election under occupation reforms. It was the first national election in which women could vote, and it produced Japan’s first cohort of women elected to the Diet.
The Tokyo Trial (IMTFE) convened to prosecute major Japanese leaders for crimes related to the war, creating a central judicial process for Allied war-crimes accountability in Japan.
Japan’s new constitution was promulgated, replacing the Meiji constitutional order via formal amendment procedures and establishing democratic institutions, expanded civil rights, and a pacifist renunciation of war.
Japan promulgated the Fundamental Law of Education, a cornerstone of occupation-era education reforms intended to align schooling with democratic principles and the new constitutional framework.
Japan enacted the Labor Standards Act, setting nationwide minimum standards for working conditions and strengthening protections for workers during the occupation’s broader democratization and social-reform agenda.
The Constitution of Japan took effect, formally launching the postwar constitutional system (including a redefined role for the emperor as symbol of the state and a new rights framework).
The Tokyo Trial issued its judgment and sentences, concluding with guilty verdicts for the remaining defendants and shaping postwar narratives of responsibility and legal accountability.
Seven condemned major war criminals, including former Prime Minister Hideki Tōjō, were hanged at Sugamo Prison under occupation authority, following confirmation of IMTFE verdicts and sentences.
Japan and 48 Allied nations signed the Treaty of Peace with Japan in San Francisco, establishing the legal basis to end the occupation and restore Japanese sovereignty (with some security arrangements handled separately).
The peace treaty entered into force, and the Allied Occupation of Japan ended, restoring Japan’s full sovereignty and concluding SCAP’s formal governing role.
Allied Occupation of Japan (1945–1952)
