What sovereign state did Avatar Aang and Fire Lord Zuko found?

The United Republic of Nations is the sovereign state founded by Avatar Aang and Fire Lord Zuko. It was created after the Hundred Year War from former Fire Nation colonies in the Earth Kingdom.

Aang and Zuko worked to resolve the political problem of colonies whose populations had become mixed over generations. Rather than forcing every resident to return to an ancestral nation, they established a new country intended to provide a home for immigrants from all four nations.

Its capital, Republic City, becomes the principal setting of The Legend of Korra. The city blends cultures, architecture, technology, and bending traditions, reflecting the founders’ vision of cooperation among the four nations. The United Republic is sometimes confused with the United Republic Council, which was its governing body before the Equalist crisis led to political reform.