Among Sangoku Domei (tripartite alliance), the Koso Alliance between the Hojo clan, which had conflicts with Kagetora in the northern Kanto region, worked as a military alliance, and dispatched troops together.
三国同盟のうち、北関東において景虎と抗争していた北条氏との甲相同盟は相互に出兵し軍事同盟として機能した。