Naruto is full of inspirations from either ancient folklore or other anime series, as indicated in various interviews with the series' author, Masashi Kishimoto. While some could surprise fans, some are pretty well-known. One of the biggest inspirations behind Naruto was the Dragon Ball series.
Its protagonist Son Goku played a key role in building the protagonist of Kishimoto's phenomenon. Moreover, other series like The Ghost in a Shell, Akira, One Piece, and Hunter x Hunter also played a key role in the making of Kishimoto's masterpiece.
But there are also certain misconceptions regarding the characters of Naruto, and two of them are centered around two Uchiha clan members. Madara was speculated by fans to be nerfed by Kaguya as he was too strong, but Kaguya was confirmed stronger than him. Moreover, Sasuke Uchiha was speculated to be inspired by Kurapika but was based on a character from Yu Yu Hakusho.
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Correcting the misconceptions behind the inspirations of some characters in Naruto
Madara Uchiha was one of the series' main antagonists. He was also one of the founders of Hidden Leaf Village, alongside Hashirama Senju and one of the first Uchiha clan members who were deeply involved in the plot.
Unfortunately, Madara disagreed with Hashirama's ideals and they had to settle their argument over a fight. Madara lost and died in front of the world, but in reality, he had gone into hiding to be reborn later on. He made preparations for his second coming, which was nothing short of perfect. He died and Obito started living by his name, showing the world that the greatest Uchiha was still alive.
He was reincarnated using Kabuto's reincarnation jutsu and waited for Obito to put everything in place. He outclassed the current Kage leaders of each clan and was so overpowered that fans presumed that Kishimoto had created a monster he had no way of killing. Fortunately, Obito wavered from his plan to give Madara a rebirth, but the antagonist forced him and was reborn.
Fortunately, Madara's thirst for power became the reason for his demise as Kaguya emerged from his body after Black Zetsu revealed his betrayal. This had the fans of the series thinking that as Kishimoto had no way of killing Madara, he used Kaguya as a way to kill him.
But this wasn't true as after Kaguya emerged from the body of Madara Uchiha, Sasuke appraised the body of Kaguya and declared her more powerful than Madara. So, the misconception that Madara was killed because Kaguya emerged from him isn't true, as Kaguya was an even stronger being than the Uchiha to start with, so she was destined to overpower him as the final antagonist of the series.
Sasuke Uchiha is the deuteragonist of the series and the person Naruto Uzumaki went out of his way to bring back home. His character is one of the most highly acclaimed characters in the series and anime. Many fans believe that it is inspired by a character from the Shounen manga series Hunter x Hunter, written and illustrated by Yoshihiro Togashi, named Kurapika.
They share the same colored eyes and share a similar background (their clan members were massacred). However, during an interview held between the two authors, Masashi Kishimoto and Yoshihiro Togashi, the author of Naruto revealed Hiei from Yu Yu Hakusho as the inspiration behind Sasuke.
Hiei is one of the protagonist of Yu Yu Hakusho. The series started its serialization in 1990 when Masashi Kishimoto enjoyed this series as a reader. He explained that he was looking into creating a "cool" character in his series and was facing problems. So, he looked into favorite characters from different series and stumbled upon Hiei, thus coming up with Sasuke Uchiha.
Hiei was a martial artist who shared a similar demeanor to Sasuke as he was a loner and didn't appreciate the weak fighters. Moreover, Hiei had eyes called the Jagan which gave him mind control, similar to Sasuke's Sharingan, and many other abilities.
So, not only was Hiei an inspiration behind the whole character, but also behind one of the famous eyes in anime, the Sharingan. But Kurapika from Hunter x Hunter could also be an inspiration behind some aspects of the Uchiha clan, as the series started its serialization before Naruto.
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