Night Battle of Kawagoe

Timeline

1. 1545–1546Kawagoe Castle · Musashi ProvinceKawagoe Castle had belonged to the Ōgigayatsu Uesugi but fell into Hōjō hands in 1537, held by Hōjō Tsunashige. In 1545, Kantō shugo Uesugi Norimasa allied with Ōgigayatsu Uesugi Tomosada to besiege the castle, and the Koga kubō Ashikaga Haruhide later joined. Ujiyori was also dealing with the Suruga Imagawa Yoshimoto front and could not immediately commit his main force to a decisive battle; the siege dragged on into the following spring.
2. 1546Around Sunakuba below Kawagoe Castle · Musashi ProvinceAfter diplomatic overtures failed, Ujiyori took the field. Traditional war tales claim he launched a night attack on the Uesugi main camp with a small force, while Tsunashige sortied from the castle simultaneously; Tomosada was killed and the coalition collapsed. Modern scholarship notes that the "80,000 against 8,000" figures and night-attack details largely derive from later texts such as the Kōyō Gunkan; primary sources can only confirm that the Hōjō army won an unexpected victory around the Sunakuba area. Whatever the tactics, the death of the Ōgigayatsu Uesugi head and the collapse of the siege are certain outcomes.
3. 1546Musashi–Kozuke · KantōThe Ōgigayatsu Uesugi clan was extinguished by this battle. Norimasa retreated to Hirai in Kozuke, and the authority of the Kantō shugo could hardly be restored; Haruhide too was forced to submit to the Hōjō. The Later Hōjō thereby gained control of Musashi and overwhelmed the old Kantō order, becoming the most powerful daimyō in Kantō for the following decades. This battle continued the Hōjō–Uesugi contest over Edo and Kawagoe that had been underway since 1524.