Summary
The World Government is the most powerful organization inOne Piece. It came into existence many centuries ago, when twenty rulers banded together to destroy the Ancient Kingdom. Naturally,the World Government made sureto hide the truth and keep the rest of the world in the dark. One of the biggest mysteries in the series is Nika.
The organization has tried its best to keep things about him a secret, but as always, truth found a way. Some characters dove into the forbidden to learn about Nika, while others had the knowledge passed on to them by their parents. The characters who know about the legendary figure have had to stay hidden as the World Government actively hunts them down.

6The Five Elders
Know About It Because Of Imu
The Five Elders are second only to Imu in terms of overall authority. Each of them hails from the twenty founding families and is fiercely devoted to the organization. The Five Elders are called Godheads, and each of them oversees a particular field. For the majority of the series, fans knew almost nothingabout the Five Elders,but that changed in the Final Saga.
Oda revealed the names of all five members and gave the audience a glimpse of their powers. As people so close to the top, the Five Elders know all about history. They are aware of Nika, as they were the first ones to mention him by name. The Five Elders also admitted that they changed the name of the Hito Hito no Mi, Model: Nika to the Gomu Gomu no Mi to hide its true nature.

5Bartholomew Kuma
Learned Through His Buccaneer Heritage
Most fans thought of Bartholomew Kuma as nothing but a cog in the grand scheme of things, but they have been forced to change their opinion after reading the Egghead arc.Bartholomew Kuma is a memberof the Buccaneer race, which is an ancient race that committed a major transgression against the World Government.
For this reason, they were hunted down and executed. Kuma learned a lot about Nika when he was only a kid, and it helped him get through the tough times. Kuma remained hopeful and continued to believe in Nika.

4Jewelry Bonney
Kuma Shared The Story With Her
Jewelry Bonney is the daughter of Ginny, aformer Revolutionary Army commander. However, Ginny could not take care of her daughter because of her untimely death. So, the responsibility fell on the shoulders of Kuma, who was more than happy to raise Bonney.
Under Kuma’s care, Bonney grew up to become a great kid. She became strong-willed and determined. When she was still five years old, Kuma told Bonney about Nika. The girl seemed to enjoy the stories very much, and she is likely aware of the entire history of the Sun God.

3Roger Pirates
Uncovered The Truth On Laugh Tale
Gol D. Roger formed his crew with the aim of conquering the Grand Land. He could not achieve his goal on his initial voyage, so he sought out Oden’s help. After the samurai joined the crew, Roger could finally learn what was written on the Poneglyphs. With Oden’s help, the crew reached Laugh Tale and found the One Piece.
Rayleigh stated that the crew also uncovered the truth about the Void Century. Roger mentioned Joy Boy by name, so it is very likely that he and the rest of the crew also learned about Nika. Given the fact that the Roger Pirates knew so much about the dark past of the World Government, it is not surprising that they were hounded even after the crew disbanded.

2Imu
One Of The Oldest Known Characters
Imu is the true sovereign of the world, who sits atop the Empty Throne. At the moment, there is little to no information available about this mysterious individual. According to Ivankov, Imu might belong to the Nerona Family, which is one of the twenty founding families of the World Government. Ivankov also insinuated that Imu might have undergone the Immortality Surgery, allowing them to stay young forever.
If that is true, then Imu knows about everything that transpired during the Void Century. They are also aware of Luffy and the power his Devil Fruit grants. So, Imu most likely knows about Nika.

1Clapp
A Fierce Believer In Nika
Clapp was a church manager who lived in the Sorbet Kingdom with his family. He was the father of Bartholomew Kuma. Clapp was a member of the Buccaneer race, and when the World Government found out about his identity, it wasted no time in capturing him. Clapp and his family were enslaved by the Celestial Dragons.
While in captivity, Clapp often told his son aboutthe Sun God, Nika, and how he was a ray of hope in dark times. It is highly likely that Nika was a member of the same race, which is why he was so popular among the Buccaneers. Unfortunately, Clapp was killed by a Celestial Dragon, leaving Kuma as the sole known survivor of the genocide of the Buccaneer race.
