Lake Biwa, Japan's largest lake, is located at the center of the province. "Ōmi" came from awaumi or "fresh-water sea" and the kanji of "Ōmi" (近江) means "an inlet near the capital" (See also Tōtōmi Province).
During the Sengoku period, the northern part of the province was the fief of Ishida Mitsunari, Tokugawa Ieyasu's opponent at the Battle of Sekigahara, although he spent most of his time in Osaka Castle administering the fief of Toyotomi Hideyoshi's young son. After Ishida's defeat, Tokugawa granted the fief to his allies, the Ii clan, who built the castle and town of Hikone from the ruins of Sawayama.
- Shiga Prefecture
- Azai District (浅井郡)
- Echi District (愛知郡)
- Gamō District (蒲生郡)
- Ika District (伊香郡) – absorbed Nishiazai District on April 1, 1897; now dissolved
- Inukami District (犬上郡)
- Kanzaki District (神崎郡) – dissolved
- Kōka District (甲賀郡) – dissolved
- Kurita District (栗太郡) – dissolved
- Sakata District (坂田郡) – dissolved
- Shiga District (滋賀郡) – dissolved
- Takashima District (高島郡) – dissolved
- Yasu District (野洲郡) – dissolved
- Nussbaum, Louis-Frédéric and Käthe Roth. (2005). Japan encyclopedia. Cambridge: Harvard University Press. ISBN 978-0-674-01753-5; OCLC 58053128
- Titsingh, Isaac. (1834). Annales des empereurs du Japon (Nihon Ōdai Ichiran). Paris: Royal Asiatic Society, Oriental Translation Fund of Great Britain and Ireland. OCLC 5850691.