One Piece is a Japanese manga series written and illustrated by Eiichiro Oda. The manga has won much praise and awards for its unique storytelling, characterization, and adventure sequence the manga series hold.
The story focuses on a boy, Monkey D Luffy, a young man made of rubber because he ate a devil fruit when he was 7 years old. The boy and his pirates were in search of a treasure named “One Piece”.
This manga series is a complete package of adventure, comedy, romance, and fun. In the manga series, the World Government is the one who controls almost all the worlds in One Piece.
The World Government uses the Navy as its primary military force, while the Cipher Pol is used for more covert operations. So, it's pretty much clear that there is a lot of importance the World Government holds.
5. Aokiji

Aokiji was the first Admiral to be revealed to the fans of the manga in One Piece. He made his entry during the Long Ring Long Island arc. Being an admiral, Aokiji’s Haki is known to be top-tier, this was seen in the manga series during the battle in Marineford.
Aokiji has the power of Hie Hie no Mi, which is a deadly Logia that has the ability to manipulate ice. After the battle of Marineford, we saw that Aokiji left the Navy, and currently, he is one of the members of the Blackbeard Pirates.
4. Akainu

He is said to be one of the strongest characters in the manga series. We saw that Akainu was a Navy Admiral before the two years of time skip and he rose to the position of Fleet Admiral after he defeated Aokiji.
Akainu is known to have tremendous durability, as he survived a fight against the strongest man in the manga which was Edward Newgate. Akainu had a lot of power of his own and was at a higher post than Aokiji which shows why he was on the top World Government list.
3. Kong

Kong is the former Fleet Admiral of the Navy who is currently the commander in chief of the World Government.
If we talk about his strength, it remains unknown, but being the former Fleet Admiral implies that he must have been at least as strong as other Navy Admiral or we can say even stronger than them.
He is one of the highest commanders in chief of the World Government. Also, Kong commanded the navy in the era of Gol D roger and whitebeard.
2. Sengoku

Sengoku is said to be a more powerful character than Akainu, Aokiji, and Kong in the whole manga. His presence has created fear even among the strongest pirates in the manga series to date.
Sengoku is known as the Buddha, as he has the power of Mythical Zoan Hito Hito no Mi, Model- Daibutsu, which enables him to turn into a giant Budha and create shockwaves at will.
He has also clashed against the likes of Roger and Whitebeard in the past, which means that he is quite an impressive fighter. Sengoku is the only Marine to have Conqueror's Haki.
1. Garp

Garp is Monkey D Luffy's grandfather, Monkey D Garp. He is known as the strongest Marine to ever live. He also owns the title of “Garp the hero”. He is also known as superior as he helped in putting an end to Rocks, one of the biggest threats to the World Government in the series.
Garps don't have any devil fruit, even though his control over Haki is tremendous and astonishing. In the manga series, he was able to fight against Gol D Roger, which just shows the fans of this series how mighty a Marine he truly is.
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