The Masamune, Sephiroths mighty blade. A weapon doesn't make the warrior, but a blade like this, well, it makes quit the impression. Sephiroth wields this weapon with great ease and is a great part of his being. Everyone, Cloud, Genesis, and all others, they know Sephiroth only like this, with the Masamune always by his side. But where did he get this marvelous weapon? That is a story on it's own.

Sephiroth was a great promise, that became clear on a very young age. Of course, the way he was created was mean't for that, to become the greatest soldier of all time. With a great warrior comes a great weapon, but Shinra did not have a weapon that would fit Sephiroth. Sephiroth tried many weapons, no guns of course, a true warrior never uses a gun, but none of the weapons he trained with could really connect with him. His incredible skill and strength reached a sort of impass, he needed a weapon, a true weapon.
Because Shinra was not going to provide him with such a weapon, Sephiroth had to go find one on his own. Soon he'd be send on serious missions, the sword he was using now would restrict him in his abillities. So he left Midgar to find a weapon, a weapon he could really bond with. Sephiroth was convinced such a weapon would exist, his teacher told him stories about how warriors could really bond with a weapon, a bond that would make you stronger. To be the best, to be the greatest, this mysterious bond between weapon and wielder must be his. The hunger for power burned deep inside him but it was only a quiet ember than. Driven by multiple reasons, Sephiroth set out to search for it, and the best place to start is Nibelheim.
Nibelheim is a vault of ancient knowledge, so many books, so many stories, there has to something that could point him in the right direction. The journey to Nibelheim is a dangerous one, but Sephiroth is a powerful warrior, especially for his age, which was sixteen. A little danger is not going to slow Sephiroth down, he lives for danger.
This journey would lead Sephiroth past Cosmo Canyon, also a place of great knowledge. Sephiroth can't let a chance to visit Cosmo Canyon slip, perhaps a answer to his question could be found there.
The knowledge he finds at Cosmo Canyon is awesome, they have incredible knowledge of the universe. Sephiroth saw amazing things there, but not the answer or clue he was looking for. This knowledge would be very useful to him in the future none the less. He continious his journey and arrives at Nibelheim not very long after his visit to Cosmo Canyon.
In Nibelheim there is a large house, called Shinra Mansion, the basement of this mansion holds a great library. Sephiroth knew for sure he could find an answer or at least a clue there. The townspeople were a bit surprised to see a young man enter the mansion, in the mansion live creepy and dangerous monsters. These creatures are no match for Sephiroth, the magic of his materia is incredibly strong.
He finds his way to the basement without any resistance, it's good training for the young soldier. The next step is going to take some time, reading the many books to find an answer. One book sparks the interest of Sephiroth, a big black book, the cover is full of dust and the pages feel old, but it's the name, the name of the book that causes Sephiroth to feel a fire in his body….Masamune. The instant Sephiroth opens this book, he knows that this is what he's been looking for.

The book speaks of an ancient blade, aade from a time long ago, the time of the Ancients. Sephiroth knows a little of this history, but every time he reads the word Ancients, a powerful and short shivering runs through his spine. He has no time to figure out why that is, he must find this weapon to achieve his true potential. The finding of this book causes the quiet ember inside him turn into a roaring fire.
Unfortunatly the book does not give a clear view of where the blade is now. But there is a small passage which catches the attention of Sephiroth:

On a day a long time ago the sun stood above the mountain directly, this way the sun does not stand for thousands of years. On this day the power of the sun can be used for creation, so on this day, takes the best smith of the Ancients his hammer and molds the power of the sun into a weapon. With the heat from the sun that could only be used on that day, a blade was made, a blade which has no equal. Controlling the heat of the sun is a very old and forgotten art, only the Ancients know this art. Time was limited and only one weapon could be made. The blade was perfect and unique. It was named after it's creator: Masamune. But no one was able to wield it the way it was intended, so it's creator stored it away, waiting for a warrior that could truly use it.

The book did not give an location of the blade, it only said that the current location, probably it's original location is unknown. It did say that the best place to find out if there are any leads: is the ninjatown Wutai. In this time with all the high-tech weaponry is Wutai an acception, blades and spears are still the towns trademark. Sephiroth doesn't hestitate and continues his journey, to the town Wutai.
The ninjatown has a unique style of buildings. Many old soldiers of the last war were able to tell Sephiroth much about old weapons, but none of the stories really helped him. But then he met this old man, he had a strange glow in his eyes. The man said he had seen the Lifestream from real close and that gave him the strange glow in his eyes. He touched the Lifestream for a second and in this moment he saw history of the Ancients. He told Sephiroth that the sun was right above Mt. Nibel that day. Somewhere this makes sense thought Sephiroth, the first Mako-Reactor, Shinra Mansion, a whole library of knowledge inside that mansion. It was the best lead Sephiroth got and so he went back to Nibelheim.
This time he would go to Mt. Nibel. The mountain is undoubtly the most dangerous place he has ever been. Fortunatly Sephiroth does not know fear and his strength is greater than a small army. Without restrain enters Sephiroth the mountain. It was strange, he didn't know why, but he got an instant feeling that the blade was close. He felt stupid because he already was so close, but no else was looking for it, so he only lost some time. He travelled deep into the mountain, fighting some fearsome monsters on the way, it was incredible how strong Sephiroth already is and the blade would only make him stronger. For some reason he now knew he was walking in the right direction, as if the blade was calling for him. Sephiroths blood started to rush through his veins, his heart was beating on a high speed, he never felt liks this before, he was always calm, no matter what. This anxiety must mean he is really close.

The closer Sephiroth came, the stronger this feeling was becoming. It was calling for him, he knew it. His feeling was correct, right in front of him was a door. The door was barely visible, because Sephiroth felt it he knew the door was there. He tried to open it, but the door would not budge. Sephiroth used powerful magic on it, but even Fire 3 had no impact. For several minutes he stood in front of the door, being silent, staring at it. At a certain point he heard some sort of voice, it seemed to be asking for a password. Sephiroth cleared his mind, yes, there was a voice and it was asking for a password, but what password.
It could not be that he came so far and not be able to reach it. Once again Sephiroth cleared his mind, he now heard a second voice, the voice of a woman, it sounded strangely familiar. Sephiroth was clueless why the voice was so soothing to him, he listened with full attention, the voice was saying: Jenova,that must be the password.
Sephiroth stood right in front of the door and said: Jenova. The door started to open, very slow and with loud screeching sounds. It took several minutes for the door to open. Sephiroth walked in to the room. The room wasn't very big and there were strange markings on the walls. These markings were new and somehow known to Sephiroth, but this wasn't important. In front of him was a large stone box, it was very old and full of dust, Sephiroth blew some of the dust of and letters became visible, it was a word, Masamune. This was it, Sephiroths body was now in a full state of anxiety.
He opened the box and there it was, a magnificent, beautiful and strong weapon. This was the missing piece of his warrior soul, now it was complete. Sephiroth felt his new found power rushing through his entire body.

Sephiroth lost much time with his search for the blade, he had to return to Midgar immediatly. But he couldn't resist to use the Masamune, Mt. Nibel is the home of some very strong monsters. He fought the monsters with even a greater ease than before, yes, this weapon was definitly it.
He rushed back to Midgar. All the way back he was thinking about his training with the other SOLDIER members, especially Genesis. Before entering this dark city he turned around, the sun was shining bright, he held the Masamune up high in the light of the sun. The blade was glowing magnificantly, what a weapon. Sephiroth stood there for 15 minutes before entering Midgar. With the Masamune as his weapon, will he definitly become the best, the best soldier there ever was! He smiled as he walked back to HQ, his glory days were about to begin.