Most of these additions are to be expected of the main character’s backstory. More details will likely continue to be introduced to Luffy’s backstory as they become relevant to the plot. Most of the significant changes to Luffy’s past are from when he was seven years old, which leaves about 16 more years to exploit for untapped storytelling potential. Some things will be planned, while others will come off as retroactive continuity; even Oda, for all his planning, must come up with stuff on the fly. In any case, Luffy’s past should be recognized for everything that can still be crammed into it.

What Kinds of Changes Have Been Made to Luffy’s Backstory?

The basis for Luffy’s backstory was covered in Chapter 1, “Romance Dawn.” Luffy had Red-Haired Shanks and his crew stationed in his hometown for a year. He ate their recently pilfered Gum-Gum Fruit that the Red-Hairs took from “an enemy ship,” got captured by mountain bandits, cost Shanks his arm, and later received his straw hat and resolved to bring it back to him. This chapter also establishes how Luffy got the scar on his cheek. The only other principal characters to appear were Makino, Woop Slap, and some of Shanks’ crewmates (Benn Beckman, Lucky Roux, Yasopp, etc.) in unnamed roles. This chapter, for everything packed into it, only provided a handful of details that could be used to inform Luffy’s backstory, or the larger One Piece narrative, for that matter. It was a relatively ambiguous first chapter meant to up the main character, his moral code, his powers, a few of his allies, and his goals.

A lot was added to the time between Shanks giving Luffy his hat and the ten years it took Luffy to set sail for himself, especially the characters. The first person to be added to Luffy’s backstory was Usopp. Luffy told his future sniper about how Yasopp would never stop talking about his son and how proud he was of him, which is how he initially recognized him. However, Yasopp appeared in Chapter 1 and never said anything about a son – he hardly even had a speaking line. Even if Usopp was planned to be the son of a Red Hair Pirate from the start, nobody could have guessed it from reading Luffy’s backstory as it was initially written.

How Luffy’s Family Has Been Changed Over the Years

Nobody could have guessed anything about Luffy’s family, either. As far as anyone could tell, he was either an orphan or had negligent or absentee parents who weren’t there to stop him from becoming a pirate. Vice Admiral (Monkey D.) Garp was introduced early via cover pages (within the first 100 chapters). However, his relationship with Luffy would remain nebulous until he was revealed as his grandfather in the Post-Enies Lobby Arc; until then, he was merely Koby and Helmeppo’s superior. A similar point can be made about (Monkey D.) Dragon the Revolutionary being Luffy’s father; that said, his saving the boy in Loguetown could have been taken as a hint. Again, while these characters may have been planned from the start, there was no way of knowing they were previously a part of Luffy’s story until the time was right.

The next family member to be added to Luffy’s story was his older brother, Portgas D. Ace. It was one thing for Luffy not to mention the grandpa he feared and the father he never met, but Ace was someone he cared about and looked up to. He mentioned Shanks plenty of times, yet this family member he had known for several years longer went unmentioned as such until the Alabasta Arc. This lack of mention arguably gets worse considering how much emphasis is put on Ace later, especially with how hard Luffy fought to prevent his execution. If Ace meant this much to Luffy, he should have mentioned him at least once without prompting. However, many are willing to chalk this up as Luffy not bothering to reflect on or talk about the past.

While plenty of readers are willing to forgive Luffy for not mentioning Garp, Dragon, or Ace to his crew, many are convinced Sabo is a genuine retcon. Despite being a second bother to Luffy, his existence was only hinted at during the Marineford Arc and confirmed after Ace’s death. It’s generally assumed that he was introduced as a substitute for Ace following the latter’s death. This is backed by his role when he enters the story’s present, especially his relationship with Luffy and his inheritance of Ace’s former Devil Fruit. Even if Luffy had a logical reason for not mentioning Sabo (he thought he was dead), it doesn’t change how convenient his introduction is.

Other Changes to Luffy’s Backstory

There have been a few more changes that have been made to Luffy’s backstory since Chapter 1. Sanks was confirmed to have a daughter named Uta in One Piece Film: Red. She was with the Red Hair Pirates when they arrived in Foosha Village and played with Luffy for a time. Her canonicity was confirmed in Chapter 1055, “The New Era.” Her existence explains Luffy’s strong desire for a musician on his crew as far back as the East Blue Saga, but that doesn’t mean Oda had her presence planned from the start; those seeds were meant more for Brook. As far as anyone knows, Oda only conceived Uta in the planning phase of Film: Red.

Another significant addition to Luffy’s story came in Chapter 1101, “To Bonney.” This and the previous Chapter, “Thank You, Bonney,” showed that Kuma visited Dawn Island (where Foosha Village was located the whole time) and caught a 16-year-old Luffy practicing his Gum-Gum Axe in the woods. This reminded him of a conversation with Dragon about his inordinate investment in a small town in the Goa Kingdom. Besides confirming that Kuma saw Luffy before he began his voyage, this also heavily implies Dragon frequented this nation to keep watch over his son from afar. This is a small detail, and its presentation makes it understandable why it wouldn’t be brought up until this chapter. However, it adds to Dragon’s character and proves he’s a caring father, whereas many would otherwise believe he completely abandoned his family to pursue life as a Revolutionary. Even if this was a retcon, its execution is reasonable.

This holds for plenty of changes to Luffy’s backstory. Even if there were no signs of these monumental aspects of his life, it’s fair to assume they wouldn’t come up unless someone prompted Luffy to talk about them. It’s the same reason he didn’t tell his crew about his true dream until Chapter 1060, “Luffy’s Dream.” The Straw Hat Captain lives in the present, so he prefers discussing things relevant at the moment.

How Luffy’s Backstory Could Change in the Future

Several areas of Luffy’s backstory must still be explored. There are about ten years between acquiring his straw hat and becoming a pirate himself. For all anyone knows, others like Kuma and Dragon observed Luffy from afar. The idea of Imu spying on his future nemesis can’t be overlooked. The series also needs to cover Luffy’s secret dream and, in all likelihood, the circumstances surrounding his birth.

Naturally, the Red Hair Pirates’ part must also be covered. Readers still must know why they stationed themselves in Foosha Village. Their intention for the Gum-Gum Fruit is a mystery (Chapter 1 suggests it wasn’t supposed to go to Luffy). While most of the significant details involving Luffy have been covered, that year in Foosha Village has as much potential as the ten years that followed.

These kinds of additions wouldn’t be considered retcons because the intrigue surrounding them has already been set up. Fans have ideas of what happened, but Oda needs to confirm or deny those suspicions within the One Piece narrative (or, if it’s not that relevant to the overarching plot, through the SBS). As long as Luffy isn’t revealed to have a third sibling, fans should be thrilled to learn about their favorite rubber pirate’s past.