Politics of Japan

Japan’s political system is a constitutional monarchy with a parliamentary government, elected legislature, and competitive multiparty elections. Its institutions operate under the Constitution of 1947.

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Constitution of Japan: Japan’s supreme law, promulgated in 1946 and effective from 1947, establishes parliamentary government and protects fundamental rights. It sets the rules for the institutions and political powers that structure Japan’s government.
Liberal Democratic Party: Japan’s conservative political party, founded in 1955 and dominant in national government for most of the postwar era. Its sustained electoral strength has made it the central force in postwar governing coalitions.
Japanese general elections: Elections that select members of Japan’s House of Representatives and determine which parties can form government. They periodically test the governing party’s mandate and determine the balance of power in the Diet.
Constitutional revision in Japan: The political process of amending Japan’s Constitution, which requires approval by the Diet and a national referendum. Debates over revision test competing views of the postwar constitutional settlement.
Postwar Japan: The period of Japanese history beginning with the country’s surrender in 1945 and its subsequent reconstruction under Allied occupation. Occupation reforms established many institutions and political conditions of the present system.
National Diet: Japan’s bicameral national legislature, consisting of the House of Representatives and the House of Councillors. It passes laws, approves budgets, and selects the prime minister.
Shigeru Yoshida: Japanese prime minister who led the country during much of its early postwar reconstruction, from 1946 to 1954. His approach to recovery and security became a durable model for postwar LDP governments.
Japanese electoral system: The rules and constituencies used to elect members of Japan’s national legislature. Its mixed electoral arrangements shape party competition and how representatives win seats.
Constitution of the Empire of Japan: Japan’s prewar constitution, in force from 1890 until its replacement in 1947, which located sovereignty in the emperor. Its imperial sovereignty contrasts with the postwar constitution’s principle of popular sovereignty.
1955 System: The post-1955 pattern in which the Liberal Democratic Party dominated government while opposition parties remained fragmented. It explains decades of stable LDP rule and the distinctive structure of party competition.