During the time of the first Uesugi, Shigefusa, they moved to Kamakura with Imperial Prince Munetaka, who was installed as Seii Taishogun (literally, "great general who subdues the barbarians") of the Kamakura Shogunate, and they became relatives of the powerful vassal family, the Ashikaga clan, through arranged marriages.
初代上杉重房のとき、鎌倉幕府の征夷大将軍に迎えられた宗尊親王に従って鎌倉へ下向し、有力御家人の足利氏と姻戚関係を結んだ。