Name : Shigekuni Yamamoto-Genryusai
Birthday : January 21
Height : 168 cm
Weight : 52 kg
Occupation : Shinigami general of the Gotei 13, captain of the 1st Division
Shigekuni Yamamoto-Genryusai is a character in the manga and anime Bleach. He is the General of the Gotei 13 and captain of the 1st Division (ichibantai, can also be translated as 'best division'). His lieutenant is Chojiro Sasakibe.
Yamamoto is depicted as an old man with a long beard. There are many scars on his torso, suggesting numerous battles in his past.
He wears the standard shinigami captain uniform, but its size seems extremely exaggerated. He doesn't seem to ever wear the sleeves of his haori, instead draping the whole thing over his body.
Like Byakuya Kuchiki and Soifon, he believes that orders must be executed without question and despises those who break the rules.
As the general of Gotei 13, Yamamoto is highly respected by several shinigami, most notably Sajin Komamura (who views Yamamoto as a benefactor who saved his life). His abilities as a shinigami are no doubt powerful, as he is able to bring 8th Division Lieutenant Nanao Ise to her knees and immobilize her with the weight of his spiritual pressure.
General Yamamoto founded the shinigami academy about 2000 years before the main Bleach storyline. It is heavily implied that this is the same shinigami academy that Renji Abarai and Rukia Kuchiki graduated from.
Yamamoto was himself a teacher at this academy, and personally instructed Shunsui Kyoraku and Jushiro Ukitake. He admits to being rather proud of Ukitake and Kyoraku and when they became captains, he "boasted about them as though they were his own sons."
Yamamoto's zanpakuto is Ryujin Jakka (lit. Flowing Blade like Flame). It is the oldest and most powerful fire-based zanpakuto and has the greatest attack power over all others in Soul Society. In sealed form, the zanpakuto is disguised as Yamamoto's staff, which disintegrates into a sword at command. When Yamamoto releases his shikai with the command Bansho Issai Kaijin to Nase (Reduce the whole of creation to smoldering ashes!), the entire blade turns to flame.
The sheer power of its aura can disintegrate anything that Yamamoto waves the sword at into ash and engulf the area in flames. However, powerful characters such as Kyoraku and Ukitake can resist this, albeit being injured in the process. Even in its initial release, its power is enough to fight against two other captains simultaneously.