Some 6,500 islands in the Gulf of Bothnia, between Finland and Sweden. They were part of Sweden until 1809, when, together with Finland, they were annexed by Russia. After the collapse of the Russian Empire in 1917, they were administered by Finland. Despite popular demands to be governed by Sweden, Finnish sovereignty was confirmed by the League of Nations in 1921. At the same time, the islands were granted considerable autonomy, since when Swedish has been the official language. In 1945, the islands' assembly again voted to come under Swedish sovereignty, but the islands' constitutional status remained unchanged.