What are the other # Areas of the Holy Empire of Britannia?
An Area is a nation or group of nations that has been conquered by
  Britannia and made into a colony. Each Area is designated with a
  number, and its people are referred to by that number. 


...


  Areas are numbered in order of conquest, though only a handful are mentioned by
  name



United States - Disputed (considering the timeline, the United
States doesn't exist in this world) In addition, Britannians make
several mentions to the "Homeland" suggesting that there's a part of
their empire that isn't an Area. Since the original colonies that
Britannian nobles fled to after losing Great Britain were in North
America, it would make sense that at least part of the United States
as well as possibly part of Canada, would be the "Homeland".
Canada and Queen Elizabeth Islands
Mexico
Greenland
Iceland
South America
Hawaii and Midway Atoll
Falkland Islands
New Zealand
Indochina - Disputed (Indochina is shown as a territory of the
 Chinese Federation)
Japan
Philippines
Cambodia - Disputed (While Britannia seems to have connections with
 Cambodia, it was never called an Area) In addition, Cambodia is
 considered a part of Indochina.
Papua New Guinea
Southern Pacific Islands
Korean Peninsula - Disputed (Shown as a territory of the Chinese
 Federation)
Indonesia - Disputed (shown as a territory of the Chinese
 Federation, especially taking part of the uprising)
Middle Eastern Federation
Unknown
Unknown
Unknown
Unknown
Unknown
Spain


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