The letter is believed to be a name that has been passed down for generations but sadly, the truth behind it hasn't been revealed in the story just yet. The people of the D are also known to be "the enemies of the Gods," making them some of the most influential and powerful characters in the story.
Updated April 4, 2022 by Rei Penber: The D Clan is one of the biggest mysteries in the world of One Piece, the answer to which will only be found upon the Straw Hat Pirates reaching Laugh Tale. Although very little is known about them, they've played a massively significant role in the overarching plot of the series.
While some characters are known to have been D members from the very beginning, others have kept this initial hidden. Given that they've played quite an important role in the story so far, we've added more information about all the known Ds in the One Piece world.
Portgas D. Rouge was the lover of the Pirate King, Gol D. Roger, and the mother of Portgas D. Ace. Roger spent his last year with Rouge and during which Ace was conceived.
Due to the World Government trying to end Roger's bloodline, Rouge had to hold Ace in his womb for 20 months, which was a feat she miraculously pulled of, likely because of her incredible willpower. When Ace was born, Rouge died immediately after, and Ace was taken care of by Garp.
Just like every D, Rouge played a very important role in the story. She was introduced in the story in Chapter 550. Rouge didn't hide her D initial by the looks of it as Sengoku openly announced her full name to the entire world.
Introduced in Nico Robin's flashback in the Enies Lobby arc of One Piece, Jaguar D. Saul was a Vice-Admiral of the Marines once. Although loyal to the World Government once, Saul started to have his doubts after hearing about the fate of the researchers of Ohara.
Eventually, Saul helped Nico Olivia escape and abandoned his position as a Vice-Admiral as well. Saul knew very little about the people of the D, but he knew that his family had carried this name for generations. Eventually, Saul was killed by Aokiji on Ohara.
Jaguar D. Saul made his introduction to the story in Chapter 392. He introduced himself to Robin as "Jaguar D. Saul," meaning he didn't hide the D in his name. Saul didn't have any information on what it meant, however.
The son of the Pirate King, Portgas D. Ace was born on Baterilla in the South Blue. Immediately after his birth, Ace was taken in by Garp and then raised by Dadan and her bandit group. Ace grew up with Luffy and Sabo and became extremely powerful with time.
Pursuing freedom and the meaning of living a life without regrets, Ace set out to sea and immediately made a name for himself. Under Whitebeard's protection, Ace rose to the position of the Second Division Commander of the crew and had his strength acknowledged by the likes of Shanks himself.
Portgas D. Ace was Luffy's brother and he made his debut towards the end of the Drum Island arc in Chapter 154. He wasn't revealed to be a D member until Chapter 157, where he met Smoker in Alabasta, who referred to him using his full name.
One of the members of the Worst Generation, Trafalgar Law was born in a town named Flevance in the North Blue. Due to the Amber Lead Disease, the entire population of the town was massacred, leaving him as the only survivor. Law was saved by Corazon and learned about the D being the enemies of the Gods.
Law trained for his entire life to take Doflamingo down and he accomplished this goal with time. Currently, he's strong enough to fight against the likes of the Yonko.
Law being a member of the D clan was a big surprise for every One Piece fan. Although he always seemed interested in the D. name, it wasn't until Chapter 763 in the Dressrosa arc that his hidden name was finally revealed. Law kept it a secret for the longest time and even now, very few people know about it.
Luffy is the protagonist of the series and he belongs to the Monkey D. family. Luffy cares very little about the D and the mystery surrounding the clan, however, he is on the path to find out the true history anyway.
As a pirate, Luffy has gone from strength to strength and become an incredible figure in the current era. He is powerful enough to take on the likes of Kaido in battle, which goes to show how far he has come.
Unsurprisingly, Luffy being a D was never a secret. From the very first chapter, Luffy introduced himself as "Monkey D. Luffy" and he continued doing so on every opportunity that he gets, even to this day.
The leader of the Revolutionary Army, Monkey D. Dragon is one of the biggest figures in the One Piece world. Concerned with bringing down the Celestial Dragons of the world, Dragon aims to fight for the sake of justice and freedom.
As the leader of one of the biggest organizations, Monkey D. Dragon also possesses tremendous strength. He's considered to be among the elites of the world and his No. 2, Sabo, is strong enough to hold his own against an Admiral.
Unlike Luffy, Monkey D. Dragon's name was kept hidden by Oda for quite a while. He made his first appearance in Chapter 100 of the story where he saved Luffy from Smoker. While Smoker did use his name, he never mentioned the family name or the D. in his title. His full name was eventually revealed by Monkey D. Garp in Chapter 432.
The captain of the Blackbeard Pirates, Marshall D. Teach is a fearsome pirate who ranks among the Yonko of the One Piece world.
Blackbeard is extremely powerful, capable of holding his own against the other Yonko. In the Grudge War, he crushed the remnants of the Whitebeard Pirates with ease and established himself as a fearsome pirate for good.
Teach was introduced during the Jaya arc of One Piece and he didn't attempt to hide his family name or his initials. Teach was introduced in the story in Chapter 223, however, his name was revealed in Chapter 234.
Known to be Roger's most formidable enemy, Rocks D. Xebec was the captain of the Rocks Pirates. Around 40 years ago, he ruled the seas of the One Piece world all alone and had the likes of Edward Newgate, Kaido, Charlotte Linlin, and even Shiki under him.
Rocks acted like a terrorist and directly opposed the World Government, something that was unheard of at the time. Eventually, he fell at the hands of Garp and Roger, who combined to take down the Rocks Pirates.
Very little is known about Rocks D. Xebec currently. The only proper mention of his name came through Sengoku in Chapter 957 of the story, where his full name was revealed to the fans. Rocks never attempted to hide being a D member, as far as what fans know so far.
Monkey D. Garp is one of the few people of the D who work for the Navy. Garp is a Vice-Admiral of the Navy and although he could've easily become an Admiral, he chose not to, simply because he hates the Celestial Dragons.
Garp is incredibly powerful and known to be the strongest Marine of all time. He is one of the very few men who were strong enough to hold their own against Pirate King Roger and earn his praise.
Monkey D. Garp was introduced quite early in the series during the "Diary of Koby-Meppo" cover story, however, his full name wasn't revealed to the fans until Chapter 432 of the story where he arrived in Water 7 to meet Luffy.
The Pirate King, Gol D. Roger was certainly one of the very strongest people in the One Piece world, if not the strongest. Roger and his crew are some of the few people who found out the true history of the world after reaching the Final Island, Laugh Tale.
In terms of strength, Roger was an absolute monster, capable of defeating Rocks Pirates with Garp's help. The only person capable of tying a battle with Roger was Whitebeard, and he did it when Roger was suffering from a terminal illness that weakened him quite a lot.
Gol D. Roger, the Pirate King, was introduced to the fans in the very first chapter. Interestingly, he was called Gold Roger by everyone as the World Government was actively trying to keep his D. lineage a secret. During the Drum Island arc, in Chapter 154, his full name and the D. initial was revealed to everyone.