Naruto's Original Father Wasn't the Fourth Hokage, it was Kurama
The initial Naruto pilot manga is vastly different from the story fans have come to know and love. The key difference is Naruto's relation to Kurama.
One of the best parts about Masashi Kishimoto's Naruto is the growth of the bond between the titular character and the nine-tailed demon fox, Kurama. At the start of the series, Kurama is depicted as a malicious entity hellbent on chaos, destruction, and hatred, but Naruto mellows him out and the two become close partners. However, the relationship between them is completely different in the original one-shot of the series.
The Naruto pilot was published in 1997 in Akamaru Jump, a branch of Shonen Jump that focuses on spotlighting one-shots. This rendition of the series is completely different from the story and world fans have come to know but establishes many of the ninja themes that are present. The series went through many revisions before becoming what it is today.
Originally, Naruto was not a ninja, but the son of the fox spirit that attacked the village on Mt. Oinari. The village chief is the sole survivor of the attack. After killing the spirit, the chief takes pity on Naruto and raises him in the village in hopes that he grows up to be less bitter and destructive than his father. To blend in, Naruto goes about his life as a mischievous human boy in search of a friend, and at the end of the pilot his true form as a fox spirit is revealed.
This is the first fox form that Naruto ever took, and it is something completely different from any of the forms in the main series. He's just a childish fox with nine tails. At first it is hard to think of him as the son of a fox spirit, but this initial depiction really drives that idea home. It's also a depiction that's reminiscent of the story and themes that would later come. Unlike his father that would use his fox powers to harm and kill, Naruto uses them to apprehend the villain and bring them to justice, showing that the chief did the right thing with taking Naruto in.
It's interesting to think about how Naruto would have turned out if Kishimoto had stuck with his original idea. Even if it made it into the actual series, Kurama being Naruto's father would have made things a lot different. Although it was short, this forgotten one-shot had some great moments, and had themes and ideas that would be expanded on in the actual series. Naruto's and Kurama's story continue in the ongoing Boruto manga.