Minowa Castle located in Minowa-cho, Takasaki City, Gunma Pref. is one of the largest medieval castles in the prefecture. The castle was built in 1526 (during the Warring States period) by Nagano Narihisa, a powerful clan in Nagano Village in Kozuke province (present-day Gunma Pref.). The Nagano clan had long served as a powerful retainer of the Uesugi clan, the Kanto Kanrei (the responsible head of the shogun’s executive office in the Kanto region). Nagano Narihisa served for Uesugi Norimasa as his right-hand man and supported him to his last breath. He also expanded his power by making kin relationship and exerting leadership and become the most powerful clan in the western part of Kozuke province. Later his son Narimori resided in the castle, but in 1566 it was attacked by Takeda Shingen and the Nagano clan was brought to extinction. Since then the castle was resided by the retainers of the Takeda clan, the retainers of Oda Nobunaga, and the Hojo clan. Finally, the castle was given to Ii Naomasa, one of the four powerful retainers of Tokugawa Ieyasu, in 1590, but its 72 years of history ended in 1598, when Naomasa moved to Takasaki Castle. The castle area covers as large as 47 ha, where stone walls, earthworks and dry moats now remain.