The Siege of Ueda Castle occurred in 1585 during the Sengoku period of Japanese history. The most powerful warlord in the land, Ieyasu Tokugawa, marched on Ueda Castle, home of the Sanada clan, due to their alliance with the Uesugi clan. Recognizing the crisis at hand, the Sanada army called for reinforcements, and Uesugi generals Kanetsugu Naoe and Keiji Maeda answered the call. In addition, Masamune Date and his retainer Magoichi Saika volunteered, although they did not formally represent the Date clan.
The large Tokugawa army succeeded in breaching the castle's walls, but they fell into a trap. Tadayo Okubo's unit was ambushed by Sanada archers, and Ieyasu ordered his forces to fall back rather than be annihilated. Just then, Yoritsuna Yazawa and Kunoichi arrived and started a fire attack against the retreating Tokugawa units, further harrying them. The Sanada forces counterattacked, and they also routed Ina, the commander of the forces laying siege to the castle.
Just then, Ujiyasu Hojo arrived with reinforcements for the Tokugawa, saying that he wanted to help out an old friend in need. However, his army was quickly routed by the Sanada forces, who proceeded to cut through his men and towards the Tokugawa main camp. Tadakatsu Honda attempted to counterattack, but he was beaten in a duel with Yukimura Sanada and forced to withdraw. Finally, Yukimura duelled with Tokugawa himself, and Tokugawa was forced to flee after being wounded. The Tokugawa army was defeated, and the Sanada clan maintained its independence.