Yonko

The Four Emperors of the Sea are four fictional powerful pirates considered great powers in Eiichiro Oda's One Piece series. In the second half of the Grand Line known as the New World, the Four Emperors rule over separate empires consisting of several islands. An alliance between two or more of the Four Emperors is feared by the World Government, which maintains hegemony over most of the world. The geopolitical struggle between the World Government and the Four Emperors is the main conflict through the story.

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