The Province of Vaasa (Finnish: Vaasan lääni, Swedish: Vasa län) was a province of Finland, established in 1775 when Finland was an integrated part of Sweden from the southern part of Ostrobothnia County and disbanded in 1996. The province was named after the city of Vaasa. In 1960 the eastern part was separated as the Province of Central Finland. In 1997 it was reunited with Central Finland, together they merged with the northern part of the Province of Häme and the Province of Turku and Pori to establish the new Province of Western Finland.