The Yonko are the four most powerful pirates in the world of One Piece. Introduced first by Garp shortly after the events of the Enies Lobby arc, the Yonko were described to be four pirates who rule the New World, the second half of the Grand Line, like Kings with no one strong enough to oppose them directly. To balance them out, an alliance between the Marines and the Shichibukai was needed, which just goes to show how powerful they truly are. Before the Paramount War, the ranks of the Yonko were made up of Shanks, Whitebeard, Kaido, and Big Mom. After the death of Whitebeard, Blackbeard rose to this position.
The world of One Piece saw a drastic shift in power after the two-year time skip when Luffy finally set out to challenge the supremacy of the Yonko and the Admirals of the Navy. During the Wano Country arc, two of the Yonko, Big Mom and Kaido, fell which triggered an era of chaos. As expected, the vacant positions had to be filled by new candidates and after a thorough process, the World Government decided to pick the four most prominent pirates in the world and dub them the new Yonko. These new Yonko include Shanks, Blackbeard, Luffy, and Buggy.
One Piece: Every Member Of The Tobiroppo, Ranked By Strength
Out of the current Four Emperors, Shanks is the oldest one, having risen to the position 6 years prior to the current events of the story. Four years before Luffy set off on his journey, Shanks became a Yonko somehow, despite having lost his apparently dominant arm. As such, he has the highest active bounty from the current Yonko which amounts to 4, 089,100,00 berries. Shanks is an incredibly powerful pirate and his crew, the Red Hair Pirates, are known to be the most balanced pirate crew with no known weaknesses.
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