Finnish-speaking majority (on the mainland), which since the 1840s had been prominent in Finland's political life, contributed to the Åland population's apprehension about its future in Finland.
Finland was, however, not willing to cede the islands and instead offered them an autonomous status. Nevertheless the residents did not approve the offer, and the dispute over the islands was submitted to the League of Nations. The latter decided that Finland should retain sovereignty over the province but that the Åland Islands should be made an autonomous territory. Thus Finland was obliged to ensure the residents of the Åland Islands the right to maintain the Swedish language, as well as their own culture and local traditions. At the same time, an international treaty established the neutral status of Åland, whereby it was prohibited to place military installations or forces on the islands.
In the course of the 20th century, increasing numbers of the islanders have perceived Finnish sovereignty as benevolent and even beneficial. The combination of disappointment about insufficient support from Sweden in the League of Nations, Swedish disrespect for Åland's demilitarized status in the 1930s, and some feelings of a shared destiny with Finland during and after World War II has changed the islanders' perception of Åland's relation to Finland from "a Swedish province in Finnish possession" to "an autonomous part of Finland". The islanders enjoyed safety at sea during WWII as their merchant fleet sailed for both the allied countries and the Germans. Consequently Åland shipping was not generally attacked as each side knew which cargo was being carried to whom.
The 150th Anniversary of Demilitarization of Åland Islands was celebrated in Finland by issuing a high value commemorative coin, the €5 150th Anniversary of Demilitarization of Åland Islands commemorative coin, minted in 2006. The obverse depicts a pine tree, very typical in the Åland
