Unification of Owari
     In 1551, Oda Nobuhide died unexpectedly, and during his funeral, Nobunaga was said to have acted outrageously, throwing the ceremonial incense at the altar. This act further alienated many Oda retainers, convincing them of Nobunaga's supposed mediocrity and lack of discipline, and they began to side with his more soft-spoken and well-mannered brother, Nobuyuki.
   Ashamed for Nobunaga's behavior, Hirate Masahide committed seppuku. This came as a huge blow to Nobunaga, who lost a mentor and a valuable retainer. He later built a temple to honor Hirate. Though Nobunaga was recognized as Nobuhide's legitimate successor, the Oda clan was divided into many factions, and even then, the entire clan was technically under Owari's true kanrei, Shiba Yoshimune. Thus, Oda Nobutomo, being Owari's deputy shugo with the powerless Shiba as his puppet, was able to challenge Nobunaga's place as Owari's new master. Nobutomo murdered Yoshimune when it was clear he supported and attempted to aid Nobunaga.
   Nobunaga successfully persuaded Oda Nobumitsu, a younger brother of Nobuhide, to join his side, however, and with Nobumitsu's help, Nobutomo was slain in Kiyosu Castle, which later became Nobunaga's place of residence for over ten years. Taking advantage of Yoshimune's son Shiba Yoshikane's position as the rightful kanrei, Nobunaga forged an alliance with the Imagawa clan of Suruga province and the Kira clan of Mikawa province, as both clans were also kanrei and would have no excuse to decline. In effect, this ensured the Imagawa would have to stop attacking Owari's borders.
   Even though Nobuyuki and his supporters were still at large, Nobunaga led an army to Mino province to aid Saito Dosan, when his son, Saito Yoshitatsu, turned against him. The campaign failed, however, as Dosan was killed and Yoshitatsu became the new master of Mino in 1556.
   A few months later, Nobuyuki, with the support of Shibata Katsuie and Hayashi Hidesada, rebelled against Nobunaga. They were defeated at the Battle of Ino. The three were pardoned with the intervention of the birth mother of Nobunaga and Nobuyuki. However, the next year, Nobuyuki again planned to rebel. Informed by Shibata Katsuie, Nobunaga faked illness and assassinated Nobuyuki in Kiyosu Castle.
   By 1559, Nobunaga had already eliminated all opposition within the clan as well as Owari province. He continued to use Shiba Yoshikane as an excuse to make peace with other daimyo, although it was later discovered that Yoshikane secretly corresponded with the Kira and Imagawa clans, trying to oust Nobunaga and restore the Shiba clan's place. Nobunaga cast him out, and alliances made in the Shiba clan's name thus became void.
Young Life/Owari/Key Events/Honnoji/ Oda Blog