Before the forgotten time or the the time before the world government, a civilization was at war.
One man that lived in this era of ninja was named Uzumaki-Namikaze Naruto. He was the jinchuuriki of the Kyuubi no Kitsune. The Fourth Great Shinobi War was fought for him but as people died on his behalf, Naruto had enough. The man that had started the war was named Tobi otherwise known as Uchiha Madara. As the war was at its peak and the Allied Shinobi Forces were about to be defeated, Naruto fought against Madara.
The teenager had seen his friends dead or critically injured, and as Naruto fought Madara, the teen unlocked a power that granted him the abilities to defeat Madara. Naruto had unlocked the Rinnengan, the same power that the sage of six paths had. The tailed beasts that had been taken already by the Akatsuki were separated and sealed into Naruto.
Naruto then resurrected his friends once the enemy was defeated. Reunited with his friends Naruto went home to celebrate with everyone. As time passed the hidden Shinobi villages grew peaceful and tensions did not rise. Even more years passed and Naruto had become great friends with hundreds of people including the Kyuubi no Kitsune but Naruto had not aged since the day he united with the Kyuubi and gained the power of the Rinnengan.
'Kyuubi, why am I not aging?' Questioned Naruto one day as he sat in his home looking at a mirror in his hands.
'I would have to think that it has something to do with bonding with my chakra as you have and bonding with the chakra of seven others too. Also as an Uzumaki, you already have a lengthened time span but it probably doesn't help that your are probably the reincarnation of the first sage and that you are a sage yourself. Take your pick but don't come complaining to me about anything odd that happens to you. You have the weirdest things that happen to you.'
Another voice sounded in Naruto's head, 'I agree with Kyuubi-sama that weird crap happens to you all the time.'
'Oh, shut up Shukaku at least he isn't as weird as you are.' Said the ichibi. This started an all out war in Naruto's head with the different tailed beasts taking different sides.
'SHUT UP! You guys are going to give me a migraine at this rate. So, be glad that you won't have to be shoved in another person for a long, long time.'
Some of the chakra beasts agreed but _ always had to disagree. 'But I don't even like you at all!'
'Oh, shut up and just don't speak again. I don't want to even here you speak again.' Said Kyuubi.
'So, what do you think I should do about my little aging problem?' Asked Naruto.
'Well, kit, the only thing I can tell you is to walk away and don't regret anything at all or you will live your life in regret and sorrow. We wouldn't want your inner world any more fucked up than it already is, cause come on, who has an inner world that's a fucking sewer? I would advise you to disappear before you watch any of your friends die of old age while you still look like a young twenty year old.'
'Your right, I can't stay here and protect this place forever.' Naruto sighed, 'I'll have to leave within the next year.'
As such, Naruto stayed for a few more years to watch his friends grow up and marry while he began to grow distant. Finally, one day, he disappeared. He simply left the village were he had grown up in.
Unfortunately, as the years passed, Naruto would wonder around the world looking for people to help yet growing ever stronger. He even slept for hundreds of years at a time. Time passed until all he had been and worked for was gone and forgotten by the people of the world. Naruto even noticed the earth splitting over the years and lands disappearing beneath the waves of the ever growing ocean. One year a war had started between two halves of the world and to end the war, Naruto created the a barrier with a Doton technique. As Naruto sat on the edge watching the world for countless centuries the strip of earth turned into what the humans called the Red Line, a line of earth that separated two halves of the world.
Animals mutated into giant sea kings while Naruto just sat and watched the world go by. He watched island communities form and governments establishing itself over all the different islands. Naruto had traveled the around the islands and anytime one took his fancy such as the island were it rains lightning or the island were humans had grown into fishmen and mermaids he carved his clan symbol which in it had the chakra seals to use the hirashin.
The years he had spent as a Shinobi had long since passed and it had been before the forgotten era of today's forgotten era. Now, Naruto mostly found himself sitting on the Red Line watching time pass him by. As time passed Naruto could sit in one place for years at a time collecting dust on his shoulders as he watched time pass.
He grew wise with the passage of time, and it helped that he had nine very powerful biju's stuck inside him. When he grew lonely and wanted human contact, Naruto could often walk across the ocean waves to get to a city were he could enjoy a quiet stroll through a town occasionally brushing against someone's shoulder or talking to an old man while sitting near a fountain.
It was during one of these times that he met Luffy and his forming crew of pirates. Naruto had traveled out of the Grand Line and had made his way to a small island were some fishmen were residing. As Naruto was talking to a strange man with a pinwheel spinning in his hat and too many scars to count, one of the fishmen began yelling.
"We hear that you're stashing swords."
"Maybe I am, it isn't illegal to collect swords." The old man said while looking away from the fishman that grabbed his neck and lifting him off the ground.
"Well I remember that having a weapon means you could be rebelling against us and that isn't allowed." The old man said but the fishman scoffed and squeezed harder onto his throat.
Naruto had just been sitting there and finally he had enough with the pissing contest the fishman was trying to start, "You do know that strangling the poor man won't get you anywhere, am I right?"
The fishman just dropped the man and said, "Why would a puny and pathetic human like you have any right to lecture me, Arlong who sailed with the sunny pirates."
"Wait, I remember you guys, you were all pretty cool as you fought the marines as you tried to go back to fishman island. Wasn't there an admiral that came after you guys or something... wait, he's an admiral now but he was a Lt. admiral when he came after you guys. I remember that Jinbei fought him off after Tiger got wounded in the surprise attack. I still can't believe that he got the jump on you at Shabbody Archipelago but you guys were okay in my book already. What are you guys doing out here. Shouldn't you be at fishman island?"
The fishman just stared at Naruto for a full minute before beginning to laugh. As the seconds rolled by the laughter just grew louder until finally he calmed down. "Who are you?
"Well, one could call me an eternally traveling sage, but I don't really travel right now but you can call me Naruto."
The fishmen just laughed while Naruto raised a questioning eyebrow, "A traveling sage, then I'm a flying bird. Now," Arlong nodded at another fishman who pointed a gun in Naruto' s face. "Why don't we get a real answer out of you."
"Hmm, I know that telling the truth is a relatively new concept for me instead of telling a bold faced lie, but I was telling the truth you know. You don't even need to point a useless toy at me either."
"Useless! How dare you disrespect us, trash!" Yelled out the nameless fishman who held the 'toy' in Naruto's face.
"For one," Naruto looked at the fishman with slits for pupils and his ki (killer intent) suffocated the poor fishman who went down on his hands and knees, "I am not trash. You may call me a demon or you may call me an abomination, but never am I trash." Naruto knelt down and got real close to the fishman's face. "Do you even know the meaning of trash?"
The fishman just shook his head while even Arlong was sweating bullets already twenty meters away. "Trash are those who abandon their comrades, their friends. I eventually had to travel the lands of my home just so I didn't have to see them age and die while I stayed in this wretched body. I never abandoned them. Now, learn your place young fishman before I put you in your place. I am from the before the forgotten era of this time' s forgotten era. I am over 50,000 years old and I grow weary of your disrespect."
Naruto stood up and looked out away from the Arlong pirates and said to himself, "It seems that the people of this time do not know me for what I am, I will have to meet with the leaders of this time so they may know my face for I am tired of the disrespect you younglings have shown me." Naruto walked toward the ocean while his ki rolled out in waves causing most people to pass out at the overwhelming feeling of death, and saw a ship with a goat for a figurehead. "Maybe they will offer me easy passage to the leaders of this time. I do not think that I have a hirashin seal set up on any government based islands."
Naruto noticed that two young men were staring at him quaking in their boots both almost ready to end their lives to get away from Naruto's ki. "Ah, young boys off to find adventure." Naruto hid his ki and walked towards the two. "Do you two know whose ship that belongs too?"
That rallied the two swordsman and they screamed in unison, "YOU WONT TAKE ZORO-ANIKI'S SHIP!"
"Woah there, I'm not taking any one's ship." Naruto tried to calm the two brothers. "I'm just wanting easy passage. I don't feel like walking towards whatever government base so I can show my face." Naruto backed up and walked away from the two amd made his way to Arlong's base. He found a very interesting scene.
A rubber man destroying Arlong Park. "Great, now how am I getting off this island." Naruto watched the fight and saw the shark man Arlong pull out his own teeth and snap at the rubber man, Naruto hopped to the top of the wall to get a clear view of the proceedings.
A blonde man who had a cigarette in his mouth just happened to see Naruto jump onto the wall. "Get down from there kid, its dangerous!"
Naruto face palmed and grabbed small shard of rock that also conveniently sat next to him. With a simple flick of his wrist, the rock was sent to the unsuspecting man. "Oh shut up, this fight is getting interesting. In all reasons, that kid is doing pretty well. He has a lot of openings but so does Arlong. What luck would have it that a heavy hitter type fighter would face a heavy hitter. Jeez if only I had that type of luck when I faced fights in my youth, maybe if they were, I wouldn't be alive. Just my rotten luck."