One Piece is a story that focuses heavily on family and the relationships between different characters. Throughout the anime/manga, the author has highlighted the role of family as being crucial. For example, take the family of the main character, Luffy.
Luffy belongs to the Monkey D. family, which is connected to the mysterious family of “D.” Only three known members of this family are recognized: Luffy, Dragon, and Garp, all of whom play significant roles within the story. However, there are a few hints throughout the plot that suggest this family has a special relationship with a hidden island in the narrative.
In One Piece, the Monkey D. family has roots from Shandora

Shandora is a mysterious land steeped in hidden history and enchantment. Initially part of Jaya Island, Shandora was propelled into Skypiea due to the Knock-Up Stream occurring 400 years prior to the main storyline. After being elevated and discovered by the inhabitants of Skypiea, its existence was continuously threatened by Skypiea’s leaders who wanted to claim this land for themselves, transforming the Shandians from a proud tribe into a marginalized group.
Yet, despite numerous challenges, the original culture and identity of the Shandians remained intact, which can be observed throughout the Skypiea arc. Notably, there are subtle hints that suggest a significant connection between the Shandians and the Monkey D. family. This initial connection can be perceived through various external clues within the narrative. In one SBS segment, Oda revealed the nationalities of the main characters, hinting that Luffy might be Brazilian, a detail that aligns closely with the Shandians drawing inspiration from Meso-American cultures.
Even the city of Shandora, which was a vast region made of gold, evokes the legendary tale of El Dorado, believed to be located in South America.

Moreover, one of the most notable connections here is Luffy’s father, Monkey D. Dragon. Many fans speculate that Dragon bears a striking resemblance to the legendary warrior Kalgara from the Shandian tribe—an important figure in the lore surrounding Mont Blanc Noland in the Skypiea arc and one of the central characters within Shandian culture. From hair and skin tone to overall appearance, there are numerous striking similarities between the two, leading many to believe that Dragon could be Kalgara’s descendant.
Additionally, the Shandians’ highest authority figure bears an intriguing resemblance to Monkey D. Garp in various ways. Not only do the two characters look alike, but the Shandian leader also wears a tattoo that resembles a dog, much like Garp’s signature dog tattoo from the early chapters of the series. Many fans believe that this is a significant hint regarding the deeper connections of this island and its ties to the Monkey D. family.

Additionally, the tattoo on the left side of Dragon’s face has raised many fans’ speculations. While many believe this is a symbol of the Revolutionary Army, a scene in Skypiea shows a statue of a Shandorian warrior that bears the same design as Dragon’s tattoo. This suggests that the tattoo may signify a deeper cultural connection, as Wiper also shares a similar tattoo style. Thus, many fans theorize that Dragon’s tattoo serves a personal significance tied to his heritage.