Ii Naomasa
In 1600, Ishida Mitsunari, born in the east of Nagahama and based in Sawayama Castle, made war against Tokugawa Ieyasu in Sekigahara, Gifu. After the battle, Ieyasu made Ii Naomasa a new lord of Sawayama. Naomasa established the Hikone Domain, later famous for Ii Naosuke. Ii Naosuke became the Tokugawa shogunate's Tairō and concluded commercial treaties with the Western powers and thus ended Japan's isolation from the world in the 19th century. Besides the Hikone Domain, many domains ruled Omi such as Zeze. With the abolition of the han system, eight prefectures were formed in Omi. They were unified into Shiga Prefecture in September 1872. "Shiga Prefecture" was named after "Shiga District" because Otsu belonged to the district until 1898. From August 1876 to February 1881, southern Fukui Prefecture had been incorporated into Shiga Prefecture.