Shigekuni Yamamoto (Tycho)

Genryūsai Shigekuni Yamamoto (山本元柳斎 重國, Yamamoto Genryūsai Shigekuni) was the captain of the 1st Division in the Gotei 13 and also the Captain-Commander of the whole Gotei 13. His lieutenant was Chōjirō Sasakibe.

He led the Gotei Faction during the Shinigami War, and was one of the three Genryūsai.

History
The man who would be known as Shigekuni Yamamoto was born as Fugaku Garyūemon Saburō (三郎臥龍右衛門富岳, Saburō Garyūemon Fugaku) of the Yamanoue Family (山上家, Yamanoue-ke), one of the Five Noble Families of early Soul Society. The Yamanoue Family occupied the mountaintop of Mt. Tenjima (天地間山, Tenjima-zan), on the outskirts of the Yanagizuku (柳憑, Willow Haunt) district of what Rukongai. As a young, Noble Shinigami, Fugaku was trained by his brothers and fathers. While Fugaku's father only referred to him as Saburō (三郎, Third Son), his brothers were less formal, and called him Fugaku or Gaku (ガク) or Little Brother (弟さん, ''Otōtosan). ''While the other Noble Families had disciplined focuses on, Hakuda, Hohō, or Kidō, the Yamanoue family boasted raw power. In addition, Fugaku's older brother, Hisakata Genkakuran Tarō Yamanoue, had created a system of standardized combat for the Shinigami with the blade, which he dubbed Kendō (剣道, Way of the Sword). While Hisakata certainly didn’t shirk traditional Shinigami practices, he simply believed in gaining power by enhancing the foundation. Hisakata trained his father and brothers in swordplay, and everyday, Fugaku heard of the tragedies happening in Yanagizuku below. Fugaku wanted to use the the military might of the Yamanoue Family to rescue and fight back against the Hollow incursions and civil unrest. Fugaku was struck for this. They were Shinigami. They didn’t deal with the base of the mountain.

In the night, a young Fugaku attempts to escape, but is stopped by his brother. They duel, and Fugaku shows off his Kendō skills against his brother, the inventor. Hisakata can easily handle his little brother, and after defending, he lands a solid palm thrust (一葉、ippa), knocking him back, dropping his sword. He tells him to rely on his sword, not its power, and then to rely on himself, not his sword. Fugaku proves himself despite losing, and Hisakata allows him to leave, though revokes his Shinigami weapon, as he is now only a Soul. He is no longer Noble, stripped of his titles, and scarred across his face. Upon reaching the base of the mountain, Fugaku renamed himself Shigekuni (重國) and got to slaying Hollows with normal swords. During his time on his musha shugyō (武者修行), he gains a lot of names. “The Man from the Mountain” (山からの男、yama kara no otoko) as well as Shigekuni of the Mountain’s Base (山本の重國, Yamamoto no Shigekuni), as opposed to the mountain’s top. This eventually evolves into a new family name, Yamamoto Shigekuni. Shige’s name was soon uttered in the same breath as other powerful warriors who were fighting back in Yanagizuku. These other two were Takahashi Ryūzaku and Nakajima Itadaki. The three became friends. After an initial falling out when the two found out Shige was once a Yamanoue, they soon rejoined one another and purified the entirety of Yanagizuku to make it safe for the inhabitants. Upon their success, they were given the name Genryūsai (元柳斎）meaning “the origin of the purified willow” referencing Yanagizuku (“haunted willow”), by the Souls they saved. While the Shinigami did little to protect the Souls of Soul Society, and enjoyed being holed up in their Seireitei walls, it was the Genryūsai who were protecting common Souls from Hollow attacks.

Eventually, a Hollow appeared that not even the power of the Genryūsai could do damage against. Luckily, this terrible creature, Malapleggio (マラプレッジオ)　abandoned Soul Society and took for the skies, never to return. After gaining fame and further power, Shigekuni decides to return to the top of the mountain to reunite with his family. To his surprise he finds a small settlement, and he talks with one of the men. He learns the Yamanoue have all but abandoned Rukongai, and have returned to Seireitei with the rest of the Noble Families. Before he leaves, Shige defeats a small attacking Hollow horde in anger. With Itadaki and Ryuzaku in tow, Shige leads the way to Seireitei, taking down anything and everything in their way. He began to feel bad for the Hollows and sought for a way to purify them. On the outskirts of Seireitei, the trio was approached by Shiba Yūtasuke (雄太助志波), a branch nobleman of the Shiba Clan. He warns them the Shinigami of Seireitei fear their approach, and that they have discovered a way to balance the Souls of the Worlds, and purify Hollows, sending them back to the World of the Living. Intrigued, Shige carried on in his quest towards Seireitei.

The city is magnificent even beyond the Yamanoue estate. Immedately upon their arrival, they are brought to a meeting with representatives of the Noble Houses. The Five Great Noble Houses are represented by Yūtasuke Shiba, Gekka Shihōin (四楓院月下)、Suzutoki Tsunayashiro (綱彌代鈴時)、Konji Kuchiki (朽木紺地), and finally Shige’s ex-brother, Hikanosei Yamanoue (山上光ノ井). There are plenty of vassal clans present as well, including the Kenjikurin (質竹林)、Kyōraku (京楽)、Ubiginu (産絹), and the Ise (伊勢). The door lock behind them, and the Genryūsai worry. Then appears a monk, who they regard as the Grandmaster of the Shinigami Order (死神体制の大師範、Shinigami Taisei no Daishihan), Ichibē Hyōsube (兵主部一兵衛). He announces the latest developments in the Shinigami system, which begin with the formation of the Royal Guard, elite shinigami who have made significant contributions to the history of Soul Society, who shall personally guard the Soul King. He starts with himself, which is met with applause. He has named everything in Soul Society including the next inventions. The next comes from a young child named Nimaiya, who has also earned the title Ōetsu (王悦, King's Rapture) from the Soul King for inventing what Ichibe has named the “zanpakutō” (斬魄刀) for its ability to cut the souls of the Hollows and purify them. Nimaiya is the only one who knows how to make them in their primitive form, the ''asauchi. ''They are swords that will get stronger over time, not weaker, as they resonate with the Reiryoku of their wielder.

The next name caught Shige’s attention, as it was none other than Yamanoue Hisakata, the inventor of Kendō as well as the first Shinigami to achieve the pinnacle of achievement in “zanjutsu”, what Ichibe is calling Bankai. He was joined by Ise Aishizu (伊勢藍巳頭), who invented what Ichibe called Kidō (鬼道), an advanced form of Nature Law (自然法). Where as shizen-hō required environmental fuel for Reiryoku spells, Kido required only the smallest particle, Reishi. There was also Kazeiro Kuchiki (朽木風色) who invented Shunpō, and Satsukiyami Shihōin (四楓院五月闇) who elevated the previous bare-handed fighting of kūken (空拳) into a spiritually enlightening path of pure strength, what Ichibe called Hakuda (白打). [These last four: Hisakata, Aishizu, Kazeiro, and Satsukiyami would come to be known as the Zeroth Yonko (零番の四功、reiban no yonkō) for inspiring the codification of Zankensōki, as well as inspiring the explicit use of the term yonkō by the nobles.] Next, they needed a Shinigami / Anti-hollow army. Ichibe then announces the official codification of the new shinigami combat system, ''zankensōki. ''