WARNING, THIS THEORY IS DISTURBING AT TIMES IN ITS DETAILS, YOU HAVE BEEN WARNED! ALSO SPOILERS!!!!!' So recently I've been curious about why the world government NEEDS to hide the void century so much. I then remembered that Oda takes inspiration from real life for One Piece. So I narrowed down my focus to Japan, and what their government hides. Have you ever heard of the slaughter of Nanking? This event took place during World War II, and many historians dub it as "The Forgoten Holocaust." Here's what happened. In World War II, Japan invaded the Chinese capital city, Nanking. The Japanese soldiers occupied the city and were ruthless. While they didn't kill nearly as many people as the German Holocaust, the methods in which the Japanese killed people were some of the most said sick and awful ways to kill people. These methods consisted of mainly decapitation, genital mutilation, and limb dismemberment. If that wasn't bad enough, the victims were innocent civilians. Men, Women, Boys, Girls, Babies, no one was spared. The entire situation was a bloodbath, just killing people randomly left and right. And if THAT wasn't bad enough, before they died, they were subject to real torture. Fathers were often forced to rape their daughters, brothers forced to rape their mothers, and grown men forced to rape incredibly young infants. And if THAT! Wasn't bad enough, the Japanese loved every second of it. The soldiers would rape Chinese women and even infants, some times AFTER mutilating their genitals. The soldiers were never condemned by the Japanese government and were even praised. There was a contest made to see who could decapitate the most civillians in a day, and it was supported in Japanese news papers. The Japanese even built walls out of decapitated heads. Hundreds of thousands of people were killed in horribly awful ways like these. After World War II, when the axis powers (Germany, Italy, and Japan) lost the war, and especially after Japan got two atom bombs, Japan needed to cover up all of its links to past events in world war II, specifically the slaughter of Nanking. TO THIS DAY Japan refuses that the slaughter of Nanking even happened, even though there are incredibly graphic photos of what happened, and testimonies of survivors. Japan is deathly serious about keeping it a secret, and keeps it out of any history documentation. And if you compare Japan pre world war II to Japan post World War II, they are very different. Pre war Japan was much more aggressive, while post war Japan is much more amicable to western society, some joking that Japan is like the 51st state. This is earily similar to the world government. The World government is very protective and secretive about the past, specifically the void century. We saw sengoku nearly have a heart attack when white beard solidified even a vague part of the past. Obviously similar to Japan denying Nanking ever happened.There's also the obvious Ohara incident when the world government killed all the scholars on Ohara. Similar to the murderous spree in Nanking, and how nanking isn't even allowed to be talked about or recorded in history books. Both the world government and Japan want to limit people's knowledge of the past, so maybe the void century is more obvious than we thought. Maybe the void century involved a ruthless extermination of the D clan, and those with the Will of D are descendents of the few survivors of the slaughter of the D clan. I believe the world government overthrew the ancient kingdom, which was ruled by the D clan, and ruthlessly slaughtered the clan. Effectively taking away the power the clan of D would have had. When Roger says "inherited will" he could be reffering to how those with the will of D were meant to rule the seas, and inherit the position of rulers of the ancient kingdom. At the end of the day, Rogers ultimate goal was to reveal the truth, and restore the power in the world to its rightful owners, the D Clan. There's also Rocinante's line, claiming that the D clan were "The natural enem[ies] of God." This could relate to how the Japanese demonized and despised the Chinese. Remember how Rocinante was a spy for the marines? And how sengoku treated him like a son? Well I think sengoku may have taught Rocinante a thing or two. Specifically, world government propaganda. Sengoku probably taught Rocinante that those with the will of d are enemies of God to demonize the remaining d clan, so that they'd be obvious targets for destruction, as they'd be the only relic of the world governments wrong doings. In Rogers early life, someone probably antagonized him because if his middle initial, maybe his whole home town, which caused him to leave and go on the run. He then met Reyleigh, and he wanted to turn the world upside down because he wanted to change the standard of D's being antagonized. As Roger journeyed, he found poneglyphs abd learned the true history of the world. And on a side note, based on this theory, the reason why Roger smiled at smoker when he was walking to the gallows was because he saw that smoker was eager to watch him die, and Roger knew that as long as other D's were alive, abd as long as they continued to seek peace and freedom, the D clan would take back their inherited thrown, and the truth would be revealed. A truth so important, that, as whitebeard said, it would bring down the government and cause a massive war, similar to how if the Japanese knew their ancestors did and supported such awful crimes, it would shatter trust in authority. In line with this theory I would also think that the revolutionaries and dragon are sort of like marines, but for the ancient kingdom, or in real life, China or Nanking, and work towards informing people and bringing it back to its formal glory. There's my first theory, share thoughts and other conclusions you can draw from this.