CIA THE WORLD FACTBOOK JAPAN 「Government ::JAPAN」には、以下のようにある。
Independence: 3 May 1947 (current constitution adopted as amendment to Meiji Constitution); notable earlier dates: 660 B.C. (traditional date of the founding of the nation by Emperor JIMMU); 29 November 1890 (Meiji Constitution provides for constitutional monarchy)
Executive branch: chief of state: Emperor AKIHITO (since 7 January 1989)
National anthem: name: "Kimigayo" (The Emperor"s Reign) lyrics/music: unknown/Hiromori HAYASHI note: adopted 1999; in use as unofficial national anthem since 1883; oldest anthem lyrics in the world, dating to the 10th century or earlier; there is some opposition to the anthem because of its association with militarism and worship of the emperor