Owari Province was a province of Japan in the area that today forms the western half of Aichi Prefecture, including the modern city of Nagoya. The province was created in 646. Owari bordered on Mikawa, Mino, and Ise Provinces. Owari and Mino provinces were separated by the Sakai River, which means "border river." The province's abbreviated name was Bishū (尾州).

Aichi Prefecture is a prefecture of Japan located in the Chūbu region of Honshū. Aichi Prefecture has a population of 7,552,873 and a geographic area of 5,172.92 square kilometres (1,997.28 sq mi) with a population density of 1,460 inhabitants per square kilometre (3,800/sq mi). Aichi Prefecture borders Mie Prefecture to the west, Gifu Prefecture and Nagano Prefecture to the north, and Shizuoka Prefecture to the east. Nagoya is the capital and largest city of the prefecture.