Sweden–Finland is a debated Finnish historiographical term referring to the Swedish Kingdom from the Kalmar Union to the Napoleonic wars, or the period from the 14th to the early 19th century. In 1809 the realm was split and the eastern half came to constitute the autonomous Grand Duchy of Finland, in personal union with Imperial Russia. The term was coined by Finnish historians during the 1920s, but since then there has been an effort to drop it from professional historiography due to its inaccuracy. However, it is often still used in everyday Finnish speech and taught in schools.