Also, in an effort to vie with Shingen, Ujimasa offered his younger brother, Saburo (later, Kagetora UESUGI), to Kenshin UESUGI, an archenemy of Ujimasa, for adoption (hostage), and established an alliance by also ceding a portion of Kozuke Province to Kenshin (the Etsu-So Alliance). また、信玄に対抗するために宿敵であった上杉謙信に、弟の三郎(後の上杉景虎)を謙信の養子(人質)として差し出し、さらに上野の支配領域を割譲して同盟を結んでいる(越相同盟)。 |