Owari, formally written as Owari no Kuni (尾張国) was an old province of Japan that is now the western half of present day Aichi prefecture. Its abbreviation is Bishu (尾州).
In 1871 with the abolition of feudal domains and the establishment of prefectures (Haihan Chiken) after the Meiji Restoration, the provinces of Owari and Mikawa were combined to eventually establish Aichi prefecture in late 1872.
Two of the most famous warlord generals of Japan's Sengoku period, Oda Nobunaga and Toyotomi Hideyoshi, were natives of Owari province.