D often comes up in the world of One Piece, with the protagonist, Monkey D. Luffy, among many others, also carrying this mysterious initial in his name. The Pirate King, Gol D. Roger was one of their members as well, and it has been implied that the D people are of utmost importance in the world of One Piece.

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While most things related to them are still shrouded in mystery, over the course of the last 900+ chapters, a good chunk of history has been revealed about these people. Here are 10 facts that you probably didn't know about the D Clan in One Piece.

10 The Will of D.

Being mentioned from the early moments in One Piece, the Will of D is something that drives all those with the initial D in their names in mysterious ways. While it is unknown whose will it really is, it is believed that someone with a D in their name will eventually fulfill it.

According to Whitebeard, Gol D. Roger is also waiting for that particular person to appear, and while that most certainly won't be Teach, someone has to take it upon himself and fulfill the mysterious Will that has, at times unknowingly, passed itself down from ages.

9 The Members

Rocks D. Xebec in One Piece.

Since information on the D people is scarce, so far only ten people have been confirmed to be its members. The latest D to have been revealed in the series is none other than the man who wished to be King of the World, Rocks D. Xebec.

Other than him, there are nine more Ds, which include the Monkey D family members, the Pirate King Roger, Teach, Portgas D. Ace, his mother Rouge, Trafalgar D. Water Law, and the former Marine Vice-Admiral Jaguar D. Saul. Over the course of time, more such members will be revealed in the series, and the fans would certainly enjoy finding out additional information about them.

8 D and Freedom

Monkey D. Dragon smiling on Island Of Baltigo in One Piece.

Almost all members of the D Clan in One Piece have an affinity for freedom. The Pirate King Gol D. Roger lived freer than anyone on the seas, and so does Monkey D. Luffy. Xebec aimed to conquer the entire world, while Dragon leads a revolution to overthrow the government itself.

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Even Saul, who was a Navy Vice-Admiral, abandoned his position because to him, it was the righteous thing to do. Meanwhile, Monkey D. Garp, another Vice-Admiral, refused the position of an Admiral several times because that would put him under the direct control of the Celestial Dragons who he despises.

7 Changing The Era

law hand death

Just like the mysterious name and the obsession with freedom, the D have often been responsible for changing the tides of the era. Rocks D. Xebec set out to conquer the entire world and had a monstrous crew using which he ruled the seas with absolute authority.

Roger became the Pirate King and found the One Piece at Raftel. Meanwhile, Blackbeard announced the beginning of his era at Marineford, while Trafalgar Law famously 'broke the gears' of the current era. Undoubtedly, there is something about the D Clan that leads its members to mess with the era and attempt to change it to their liking.

6 The Storm Bringers

Mentioned first by Trafalgar Law, it is widely believed that the D cause events that disrupt the peace of those who capitalize on power. Over the years, several D clan members have taken part in events that the World Government has despised.

The Gorosei, also known as the Five Elder Stars, are often worried about the people of the D who, according to them, often show up from time to time to throw the world into a state of chaos. To hide the facts, the Government often covered up those with the D initial, such as Gol D. Roger's name being turned into 'Gold Roger' instead.

5 The Meaning of D

An up-close shot of Gol D Roger in One Piece

Although it may appear to some as just an initial. The D certainly does hold a meaning. Curious about its meaning, some fans tried to ask Oda what it meant in an SBS, and as expected, Oda said that he would reveal its meaning when the right time arrives.

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For now, it's just a D. However, there is a hidden meaning behind it, which we'll find out one day. Some fans theorize the D means 'Demon' or 'Devil', but no conclusive proof has been found to date.

4 Natural Enemy of God

One Piece has always promoted the D people as the natural enemies of God for some reason. During the Skypiea arc, Enel, the main antagonist, called himself God and the person who stood in his way was none other than Monkey D. Luffy.

Further backing to this was provided at Dressrosa, where Donquixote Doflamingo, a Celestial Dragon (basically Godly in stature), was taken down by Luffy. According to Rosinante, the people with the D initial in their names are God's natural enemies, and they show up often to throw their plans into absolute tatters.

3 The D Families

Among those who carry the D initial in their name are people who belong to various families. The Monkey family includes Garp, Dragon, and Luffy, while the Gol family included Roger and Ace.

According to Rosinante, the D secretly spread throughout the world since a long time ago and thus, a large number of people possess this name now. In fact, even the Giants, like Saul are a part of the D clan, which just goes to show the diversity the name has taken over the years. Some choose to openly display it, like Luffy, while others, such as Law, try to keep their name a secret.

2 The Inherited Will

Monkey D. Luffy holding his iconic Straw Hat and smiling during One Piece

The Will of D cannot be extinguished, ever. If there's one thing that the series has taught us, it's that will, specifically, the Will of D is inherited. Even if a D clan member dies, the flames of their will aren't extinguished. Instead, someone else takes over from them to fulfill what the will truly is.

According to both Gol D. Roger and Whitebeard, the Will of D will eventually be fulfilled when someone finds the One Piece treasure, and eventually, the world will turn upside down because of it.

1 The Fearless Smile of the D

When faced by death, everyone looks grim, except for the people who bear D in their names. Surprisingly, these people show no fear of death. Instead, they choose not to surrender to power and smile in its face, even if death is inevitable.

This was observed when Gol D. Roger, and after him, Ace died. Jaguar D. Saul died with a smile on his face as well. Similarly, Luffy, at his execution at Logue Town, didn't particularly care about the fact that he was dying. Smoker was surprised to see him smile when faced by death, akin to the Pirate King.

NEXT: One Piece: 5 Characters Who Can Defeat Rocks D. Xebec (& 5 Who Can't)