United States of Japan

Area 11, formerly known as Japan, is the primary setting of the Code Geass Anime throughout both seasons. Presumably, Japan's history in the Code Geass Universe is little different from in the real world.

Prior to it's invasion and occupation, Japan used the real-world red dot flag, and had adopted a parliamentary system (unique in this universe) of goverment, having abandoned the Emperor's rule earlier. Surprisingly, the Japanese nation seems to have avoided becoming a subject of the Chinese Federation, despite nations as far away as Pakistan and as large as India becoming members. This Japan seems never to have undergone an Imperial Expansive period as did real-world Japan in WWII.

Ultimately, this may have been to their disadvantage, for when Japan's exploitation of the limited Sakuradite mineral export sparked the Second Pacific War, the Britannian Armed forced easily overwhelmed the unsupported nation's defenses.

Upon Britannian occupation, Japan was renamed Area 11, the Japanese people becoming "Elevens", and retains that name to today. Britannia quickly began building colonies and mines on the island, and recruiting former Japanese as "Honorary Britannians". Japanese Terrorist organizations, such as the Japanese Liberation Front, continued to pose a constant but fairly minor threat to Britannian settlers until the appearance of Zero, after which most of the rebels were either defeated or recruited into the Black Knights.

After the failure of the Black Rebellion, Area 11 is designated a "Correctional Area" and particularly heavy penalties are levied at the Elevens as punishment for their role in the uprising.

With Zero's return, Zero declares the "United State of Japan", which he had planned to form during the Black Rebellion. The approximate one million citizens of the USJ - all members of the Black Knights - he manages to exodus to an artificial Island Granted to them by the Chinese Federation. The USJ, though it holds no territory in actual Japan, now works closely with the Chinese Empress following the deaths of the Eunuch Generals, attempting to keep control over the now disintegrating Empire.