With pirates running around and the World Government relentlessly chasing and clashing with them, the world of One Piece is in constant turmoil. It sees countless epic battles of varying scales — the Marineford War being one of its biggest battles yet — participated by powerful individuals from different forces. That being said, characters within the One Piece universe are defined not only by their strengths but also by their prestigious titles.
Source：https://www.cbr.com/one-piece-highest-ranking-titles-meanings-captain-yonko/
