Nobunaga’s former allies turn against him in fear of the rise of a strong central authority.
When civil war erupts in 1570, remaining Nobunaga loyalists include only Tokugawa Iyeyasu, daimyo of Mikawa, and minor daimyos of Ise.
When Nobunaga launches a campaign into the Asakura clan's domain, Azai Nagamasa, to whom his sister Oichi is married, breaks the alliance with Oda to honor the Azai-Asakura alliance which has lasted for generations.
The anti-Nobunaga alliance, with the help of Ikko rebels—a small, militant, offshoot from Jodo Shinshu Buddhism—springs into full force, taking a heavy toll on the Oda clan.
Nobunaga, along with Tokugawa Ieyasu, lays siege to the castles of Odani and Yokoyama, the fortresses of the Asai and Asakura families.
As warriors pour from the castles, the battle becomes a melee fought in the middle of the shallow river.
For a time, Nobunaga's forces, supplemented by five hundred arquebusiers, fight the Asai, while the Tokugawa warriors battle the Asakura a short distance upstream.
After the Tokugawa forces finish off the Asakura, they then turn and attack the Asai right flank.
Inaba Ittetsu, who had been held in reserve, now advances to strike the Asai left flank.
Many of the besiegers of Yokoyama even leave their positions to aid in the battle, which ends in defeat for the combined forces of the Asakura and Azai clans.
Nobunga’s military commander Shibata Katsuie, once betrothed to his sister Oichi, is not present at the battle of Anegawa as he is besieged at Chokoji Castle by four thousand Rokkakku soldiers; he eventually wins via an all-out attack that inspires the Rokkakku to retreat; this, along with a series of brilliant victories, gains him renown as "Oni Shibata".
